Shrink the size of Expr (#12610)

# Description
Continuing from #12568, this PR further reduces the size of `Expr` from
64 to 40 bytes. It also reduces `Expression` from 128 to 96 bytes and
`Type` from 32 to 24 bytes.

This was accomplished by:
- for `Expr` with multiple fields (e.g., `Expr::Thing(A, B, C)`),
merging the fields into new AST struct types and then boxing this struct
(e.g. `Expr::Thing(Box<ABC>)`).
- replacing `Vec<T>` with `Box<[T]>` in multiple places. `Expr`s and
`Expression`s should rarely be mutated, if at all, so this optimization
makes sense.

By reducing the size of these types, I didn't notice a large performance
improvement (at least compared to #12568). But this PR does reduce the
memory usage of nushell. My config is somewhat light so I only noticed a
difference of 1.4MiB (38.9MiB vs 37.5MiB).

---------

Co-authored-by: Stefan Holderbach <sholderbach@users.noreply.github.com>

crates/nu-cli/src/commands/keybindings_default.rs

@@ -12,7 +12,7 @@ impl Command for KeybindingsDefault {
     fn signature(&self) -> Signature {
         Signature::build(self.name())
             .category(Category::Platform)
-            .input_output_types(vec![(Type::Nothing, Type::Table(vec![]))])
+            .input_output_types(vec![(Type::Nothing, Type::table())])
     }
 
     fn usage(&self) -> &str {

crates/nu-cli/src/commands/keybindings_list.rs

@@ -14,7 +14,7 @@ impl Command for KeybindingsList {
 
     fn signature(&self) -> Signature {
         Signature::build(self.name())
-            .input_output_types(vec![(Type::Nothing, Type::Table(vec![]))])
+            .input_output_types(vec![(Type::Nothing, Type::table())])
             .switch("modifiers", "list of modifiers", Some('m'))
             .switch("keycodes", "list of keycodes", Some('k'))
             .switch("modes", "list of edit modes", Some('o'))

crates/nu-cli/src/syntax_highlight.rs

@@ -361,7 +361,7 @@ fn find_matching_block_end_in_expr(
             Expr::Nothing => None,
             Expr::Garbage => None,
 
-            Expr::Table(hdr, rows) => {
+            Expr::Table(table) => {
                 if expr_last == global_cursor_offset {
                     // cursor is at table end
                     Some(expr_first)
@@ -370,11 +370,11 @@ fn find_matching_block_end_in_expr(
                     Some(expr_last)
                 } else {
                     // cursor is inside table
-                    for inner_expr in hdr {
+                    for inner_expr in table.columns.as_ref() {
                         find_in_expr_or_continue!(inner_expr);
                     }
-                    for row in rows {
-                        for inner_expr in row {
+                    for row in table.rows.as_ref() {
+                        for inner_expr in row.as_ref() {
                             find_in_expr_or_continue!(inner_expr);
                         }
                     }

crates/nu-cmd-dataframe/src/dataframe/eager/to_nu.rs

@@ -24,7 +24,7 @@ impl Command for ToNu {
             .switch("tail", "shows tail rows", Some('t'))
             .input_output_types(vec![
                 (Type::Custom("expression".into()), Type::Any),
-                (Type::Custom("dataframe".into()), Type::Table(vec![])),
+                (Type::Custom("dataframe".into()), Type::table()),
             ])
             //.input_output_type(Type::Any, Type::Any)
             .category(Category::Custom("dataframe".into()))

crates/nu-cmd-extra/src/extra/bits/into.rs

@@ -30,8 +30,8 @@ impl Command for BitsInto {
                 (Type::Duration, Type::String),
                 (Type::String, Type::String),
                 (Type::Bool, Type::String),
-                (Type::Table(vec![]), Type::Table(vec![])),
-                (Type::Record(vec![]), Type::Record(vec![])),
+                (Type::table(), Type::table()),
+                (Type::record(), Type::record()),
             ])
             .allow_variants_without_examples(true) // TODO: supply exhaustive examples
             .rest(

crates/nu-cmd-extra/src/extra/conversions/fmt.rs

@@ -15,7 +15,7 @@ impl Command for Fmt {
 
     fn signature(&self) -> nu_protocol::Signature {
         Signature::build("fmt")
-            .input_output_types(vec![(Type::Number, Type::Record(vec![]))])
+            .input_output_types(vec![(Type::Number, Type::record())])
             .category(Category::Conversions)
     }
 

crates/nu-cmd-extra/src/extra/filters/roll/roll_down.rs

@@ -16,7 +16,7 @@ impl Command for RollDown {
     fn signature(&self) -> Signature {
         Signature::build(self.name())
             // TODO: It also operates on List
-            .input_output_types(vec![(Type::Table(vec![]), Type::Table(vec![]))])
+            .input_output_types(vec![(Type::table(), Type::table())])
             .named("by", SyntaxShape::Int, "Number of rows to roll", Some('b'))
             .category(Category::Filters)
     }

crates/nu-cmd-extra/src/extra/filters/roll/roll_left.rs

@@ -16,8 +16,8 @@ impl Command for RollLeft {
     fn signature(&self) -> Signature {
         Signature::build(self.name())
             .input_output_types(vec![
-                (Type::Record(vec![]), Type::Record(vec![])),
-                (Type::Table(vec![]), Type::Table(vec![])),
+                (Type::record(), Type::record()),
+                (Type::table(), Type::table()),
             ])
             .named(
                 "by",

crates/nu-cmd-extra/src/extra/filters/roll/roll_right.rs

@@ -16,8 +16,8 @@ impl Command for RollRight {
     fn signature(&self) -> Signature {
         Signature::build(self.name())
             .input_output_types(vec![
-                (Type::Record(vec![]), Type::Record(vec![])),
-                (Type::Table(vec![]), Type::Table(vec![])),
+                (Type::record(), Type::record()),
+                (Type::table(), Type::table()),
             ])
             .named(
                 "by",

crates/nu-cmd-extra/src/extra/filters/roll/roll_up.rs

@@ -16,7 +16,7 @@ impl Command for RollUp {
     fn signature(&self) -> Signature {
         Signature::build(self.name())
             // TODO: It also operates on List
-            .input_output_types(vec![(Type::Table(vec![]), Type::Table(vec![]))])
+            .input_output_types(vec![(Type::table(), Type::table())])
             .named("by", SyntaxShape::Int, "Number of rows to roll", Some('b'))
             .category(Category::Filters)
     }

crates/nu-cmd-extra/src/extra/filters/rotate.rs

@@ -11,8 +11,8 @@ impl Command for Rotate {
     fn signature(&self) -> Signature {
         Signature::build("rotate")
             .input_output_types(vec![
-                (Type::Record(vec![]), Type::Table(vec![])),
-                (Type::Table(vec![]), Type::Table(vec![])),
+                (Type::record(), Type::table()),
+                (Type::table(), Type::table()),
             ])
             .switch("ccw", "rotate counter clockwise", None)
             .rest(

crates/nu-cmd-extra/src/extra/filters/update_cells.rs

@@ -12,7 +12,7 @@ impl Command for UpdateCells {
 
     fn signature(&self) -> Signature {
         Signature::build("update cells")
-            .input_output_types(vec![(Type::Table(vec![]), Type::Table(vec![]))])
+            .input_output_types(vec![(Type::table(), Type::table())])
             .required(
                 "closure",
                 SyntaxShape::Closure(Some(vec![SyntaxShape::Any])),

crates/nu-cmd-extra/src/extra/formats/from/url.rs

@@ -10,7 +10,7 @@ impl Command for FromUrl {
 
     fn signature(&self) -> Signature {
         Signature::build("from url")
-            .input_output_types(vec![(Type::String, Type::Record(vec![]))])
+            .input_output_types(vec![(Type::String, Type::record())])
             .category(Category::Formats)
     }
 

crates/nu-cmd-extra/src/extra/platform/ansi/gradient.rs

@@ -46,8 +46,8 @@ impl Command for SubCommand {
                     Type::List(Box::new(Type::String)),
                     Type::List(Box::new(Type::String)),
                 ),
-                (Type::Table(vec![]), Type::Table(vec![])),
-                (Type::Record(vec![]), Type::Record(vec![])),
+                (Type::table(), Type::table()),
+                (Type::record(), Type::record()),
             ])
             .allow_variants_without_examples(true)
             .category(Category::Platform)

crates/nu-cmd-extra/src/extra/strings/encode_decode/decode_hex.rs

@@ -17,8 +17,8 @@ impl Command for DecodeHex {
                     Type::List(Box::new(Type::String)),
                     Type::List(Box::new(Type::Binary)),
                 ),
-                (Type::Table(vec![]), Type::Table(vec![])),
-                (Type::Record(vec![]), Type::Record(vec![])),
+                (Type::table(), Type::table()),
+                (Type::record(), Type::record()),
             ])
             .allow_variants_without_examples(true)
             .rest(

crates/nu-cmd-extra/src/extra/strings/encode_decode/encode_hex.rs

@@ -17,8 +17,8 @@ impl Command for EncodeHex {
                     Type::List(Box::new(Type::Binary)),
                     Type::List(Box::new(Type::String)),
                 ),
-                (Type::Table(vec![]), Type::Table(vec![])),
-                (Type::Record(vec![]), Type::Record(vec![])),
+                (Type::table(), Type::table()),
+                (Type::record(), Type::record()),
             ])
             .allow_variants_without_examples(true)
             .rest(

crates/nu-cmd-extra/src/extra/strings/format/command.rs

@@ -13,8 +13,8 @@ impl Command for FormatPattern {
     fn signature(&self) -> Signature {
         Signature::build("format pattern")
             .input_output_types(vec![
-                (Type::Table(vec![]), Type::List(Box::new(Type::String))),
-                (Type::Record(vec![]), Type::Any),
+                (Type::table(), Type::List(Box::new(Type::String))),
+                (Type::record(), Type::Any),
             ])
             .required(
                 "pattern",

crates/nu-cmd-extra/src/extra/strings/str_/case/camel_case.rs

@@ -18,8 +18,8 @@ impl Command for SubCommand {
                     Type::List(Box::new(Type::String)),
                     Type::List(Box::new(Type::String)),
                 ),
-                (Type::Table(vec![]), Type::Table(vec![])),
-                (Type::Record(vec![]), Type::Record(vec![])),
+                (Type::table(), Type::table()),
+                (Type::record(), Type::record()),
             ])
             .allow_variants_without_examples(true)
             .rest(

crates/nu-cmd-extra/src/extra/strings/str_/case/kebab_case.rs

@@ -14,8 +14,8 @@ impl Command for SubCommand {
         Signature::build("str kebab-case")
             .input_output_types(vec![
                 (Type::String, Type::String),
-                (Type::Table(vec![]), Type::Table(vec![])),
-                (Type::Record(vec![]), Type::Record(vec![])),
+                (Type::table(), Type::table()),
+                (Type::record(), Type::record()),
                 (
                     Type::List(Box::new(Type::String)),
                     Type::List(Box::new(Type::String)),

crates/nu-cmd-extra/src/extra/strings/str_/case/pascal_case.rs

@@ -14,8 +14,8 @@ impl Command for SubCommand {
         Signature::build("str pascal-case")
             .input_output_types(vec![
                 (Type::String, Type::String),
-                (Type::Table(vec![]), Type::Table(vec![])),
-                (Type::Record(vec![]), Type::Record(vec![])),
+                (Type::table(), Type::table()),
+                (Type::record(), Type::record()),
                 (
                     Type::List(Box::new(Type::String)),
                     Type::List(Box::new(Type::String)),

crates/nu-cmd-extra/src/extra/strings/str_/case/screaming_snake_case.rs

@@ -18,8 +18,8 @@ impl Command for SubCommand {
                     Type::List(Box::new(Type::String)),
                     Type::List(Box::new(Type::String)),
                 ),
-                (Type::Table(vec![]), Type::Table(vec![])),
-                (Type::Record(vec![]), Type::Record(vec![])),
+                (Type::table(), Type::table()),
+                (Type::record(), Type::record()),
             ])
             .allow_variants_without_examples(true)
             .rest(

crates/nu-cmd-extra/src/extra/strings/str_/case/snake_case.rs

@@ -18,8 +18,8 @@ impl Command for SubCommand {
                     Type::List(Box::new(Type::String)),
                     Type::List(Box::new(Type::String)),
                 ),
-                (Type::Table(vec![]), Type::Table(vec![])),
-                (Type::Record(vec![]), Type::Record(vec![])),
+                (Type::table(), Type::table()),
+                (Type::record(), Type::record()),
             ])
             .allow_variants_without_examples(true)
             .rest(

crates/nu-cmd-extra/src/extra/strings/str_/case/title_case.rs

@@ -18,8 +18,8 @@ impl Command for SubCommand {
                     Type::List(Box::new(Type::String)),
                     Type::List(Box::new(Type::String)),
                 ),
-                (Type::Table(vec![]), Type::Table(vec![])),
-                (Type::Record(vec![]), Type::Record(vec![])),
+                (Type::table(), Type::table()),
+                (Type::record(), Type::record()),
             ])
             .allow_variants_without_examples(true)
             .rest(

crates/nu-cmd-lang/src/core_commands/lazy_make.rs

@@ -15,7 +15,7 @@ impl Command for LazyMake {
 
     fn signature(&self) -> Signature {
         Signature::build("lazy make")
-            .input_output_types(vec![(Type::Nothing, Type::Record(vec![]))])
+            .input_output_types(vec![(Type::Nothing, Type::record())])
             .required_named(
                 "columns",
                 SyntaxShape::List(Box::new(SyntaxShape::String)),

crates/nu-cmd-lang/src/core_commands/version.rs

@@ -16,7 +16,7 @@ impl Command for Version {
 
     fn signature(&self) -> Signature {
         Signature::build("version")
-            .input_output_types(vec![(Type::Nothing, Type::Record(vec![]))])
+            .input_output_types(vec![(Type::Nothing, Type::record())])
             .allow_variants_without_examples(true)
             .category(Category::Core)
     }

crates/nu-cmd-plugin/src/commands/plugin/list.rs

@@ -13,14 +13,17 @@ impl Command for PluginList {
         Signature::build("plugin list")
             .input_output_type(
                 Type::Nothing,
-                Type::Table(vec![
-                    ("name".into(), Type::String),
-                    ("is_running".into(), Type::Bool),
-                    ("pid".into(), Type::Int),
-                    ("filename".into(), Type::String),
-                    ("shell".into(), Type::String),
-                    ("commands".into(), Type::List(Type::String.into())),
-                ]),
+                Type::Table(
+                    [
+                        ("name".into(), Type::String),
+                        ("is_running".into(), Type::Bool),
+                        ("pid".into(), Type::Int),
+                        ("filename".into(), Type::String),
+                        ("shell".into(), Type::String),
+                        ("commands".into(), Type::List(Type::String.into())),
+                    ]
+                    .into(),
+                ),
             )
             .category(Category::Plugin)
     }

crates/nu-command/src/bytes/add.rs

@@ -31,8 +31,8 @@ impl Command for BytesAdd {
                     Type::List(Box::new(Type::Binary)),
                     Type::List(Box::new(Type::Binary)),
                 ),
-                (Type::Table(vec![]), Type::Table(vec![])),
-                (Type::Record(vec![]), Type::Record(vec![])),
+                (Type::table(), Type::table()),
+                (Type::record(), Type::record()),
             ])
             .allow_variants_without_examples(true)
             .required("data", SyntaxShape::Binary, "The binary to add.")

crates/nu-command/src/bytes/at.rs

@@ -41,8 +41,8 @@ impl Command for BytesAt {
                     Type::List(Box::new(Type::Binary)),
                     Type::List(Box::new(Type::Binary)),
                 ),
-                (Type::Table(vec![]), Type::Table(vec![])),
-                (Type::Record(vec![]), Type::Record(vec![])),
+                (Type::table(), Type::table()),
+                (Type::record(), Type::record()),
             ])
             .required("range", SyntaxShape::Range, "The range to get bytes.")
             .rest(

crates/nu-command/src/bytes/ends_with.rs

@@ -24,8 +24,8 @@ impl Command for BytesEndsWith {
     fn signature(&self) -> Signature {
         Signature::build("bytes ends-with")
             .input_output_types(vec![(Type::Binary, Type::Bool),
-                (Type::Table(vec![]), Type::Table(vec![])),
-                (Type::Record(vec![]), Type::Record(vec![])),
+                (Type::table(), Type::table()),
+                (Type::record(), Type::record()),
             ])
             .allow_variants_without_examples(true)
             .required("pattern", SyntaxShape::Binary, "The pattern to match.")

crates/nu-command/src/bytes/index_of.rs

@@ -28,8 +28,8 @@ impl Command for BytesIndexOf {
                 (Type::Binary, Type::Any),
                 // FIXME: this shouldn't be needed, cell paths should work with the two
                 // above
-                (Type::Table(vec![]), Type::Table(vec![])),
-                (Type::Record(vec![]), Type::Record(vec![])),
+                (Type::table(), Type::table()),
+                (Type::record(), Type::record()),
             ])
             .allow_variants_without_examples(true)
             .required(

crates/nu-command/src/bytes/length.rs

@@ -17,8 +17,8 @@ impl Command for BytesLen {
                     Type::List(Box::new(Type::Binary)),
                     Type::List(Box::new(Type::Int)),
                 ),
-                (Type::Table(vec![]), Type::Table(vec![])),
-                (Type::Record(vec![]), Type::Record(vec![])),
+                (Type::table(), Type::table()),
+                (Type::record(), Type::record()),
             ])
             .allow_variants_without_examples(true)
             .rest(

crates/nu-command/src/bytes/remove.rs

@@ -26,8 +26,8 @@ impl Command for BytesRemove {
         Signature::build("bytes remove")
             .input_output_types(vec![
                 (Type::Binary, Type::Binary),
-                (Type::Table(vec![]), Type::Table(vec![])),
-                (Type::Record(vec![]), Type::Record(vec![])),
+                (Type::table(), Type::table()),
+                (Type::record(), Type::record()),
             ])
             .required("pattern", SyntaxShape::Binary, "The pattern to find.")
             .rest(

crates/nu-command/src/bytes/replace.rs

@@ -26,8 +26,8 @@ impl Command for BytesReplace {
         Signature::build("bytes replace")
             .input_output_types(vec![
                 (Type::Binary, Type::Binary),
-                (Type::Table(vec![]), Type::Table(vec![])),
-                (Type::Record(vec![]), Type::Record(vec![])),
+                (Type::table(), Type::table()),
+                (Type::record(), Type::record()),
             ])
             .allow_variants_without_examples(true)
             .required("find", SyntaxShape::Binary, "The pattern to find.")

crates/nu-command/src/bytes/reverse.rs

@@ -13,8 +13,8 @@ impl Command for BytesReverse {
         Signature::build("bytes reverse")
             .input_output_types(vec![
                 (Type::Binary, Type::Binary),
-                (Type::Table(vec![]), Type::Table(vec![])),
-                (Type::Record(vec![]), Type::Record(vec![])),
+                (Type::table(), Type::table()),
+                (Type::record(), Type::record()),
             ])
             .allow_variants_without_examples(true)
             .rest(

crates/nu-command/src/bytes/starts_with.rs

@@ -25,8 +25,8 @@ impl Command for BytesStartsWith {
         Signature::build("bytes starts-with")
             .input_output_types(vec![
                 (Type::Binary, Type::Bool),
-                (Type::Table(vec![]), Type::Table(vec![])),
-                (Type::Record(vec![]), Type::Record(vec![])),
+                (Type::table(), Type::table()),
+                (Type::record(), Type::record()),
             ])
             .allow_variants_without_examples(true)
             .required("pattern", SyntaxShape::Binary, "The pattern to match.")

crates/nu-command/src/charting/histogram.rs

@@ -19,7 +19,7 @@ impl Command for Histogram {
 
     fn signature(&self) -> Signature {
         Signature::build("histogram")
-            .input_output_types(vec![(Type::List(Box::new(Type::Any)), Type::Table(vec![])),])
+            .input_output_types(vec![(Type::List(Box::new(Type::Any)), Type::table()),])
             .optional("column-name", SyntaxShape::String, "Column name to calc frequency, no need to provide if input is a list.")
             .optional("frequency-column-name", SyntaxShape::String, "Histogram's frequency column, default to be frequency column output.")
             .named("percentage-type", SyntaxShape::String, "percentage calculate method, can be 'normalize' or 'relative', in 'normalize', defaults to be 'normalize'", Some('t'))

crates/nu-command/src/conversions/into/binary.rs

@@ -30,8 +30,8 @@ impl Command for SubCommand {
                 (Type::Bool, Type::Binary),
                 (Type::Filesize, Type::Binary),
                 (Type::Date, Type::Binary),
-                (Type::Table(vec![]), Type::Table(vec![])),
-                (Type::Record(vec![]), Type::Record(vec![])),
+                (Type::table(), Type::table()),
+                (Type::record(), Type::record()),
             ])
             .allow_variants_without_examples(true) // TODO: supply exhaustive examples
             .switch("compact", "output without padding zeros", Some('c'))

crates/nu-command/src/conversions/into/bool.rs

@@ -16,9 +16,9 @@ impl Command for SubCommand {
                 (Type::Number, Type::Bool),
                 (Type::String, Type::Bool),
                 (Type::Bool, Type::Bool),
-                (Type::List(Box::new(Type::Any)), Type::Table(vec![])),
-                (Type::Table(vec![]), Type::Table(vec![])),
-                (Type::Record(vec![]), Type::Record(vec![])),
+                (Type::List(Box::new(Type::Any)), Type::table()),
+                (Type::table(), Type::table()),
+                (Type::record(), Type::record()),
             ])
             .allow_variants_without_examples(true)
             .rest(

crates/nu-command/src/conversions/into/cell_path.rs

@@ -15,10 +15,9 @@ impl Command for IntoCellPath {
                 (Type::Int, Type::CellPath),
                 (Type::List(Box::new(Type::Any)), Type::CellPath),
                 (
-                    Type::List(Box::new(Type::Record(vec![
-                        ("value".into(), Type::Any),
-                        ("optional".into(), Type::Bool),
-                    ]))),
+                    Type::List(Box::new(Type::Record(
+                        [("value".into(), Type::Any), ("optional".into(), Type::Bool)].into(),
+                    ))),
                     Type::CellPath,
                 ),
             ])

crates/nu-command/src/conversions/into/datetime.rs

@@ -62,8 +62,8 @@ impl Command for SubCommand {
             (Type::Int, Type::Date),
             (Type::String, Type::Date),
             (Type::List(Box::new(Type::String)), Type::List(Box::new(Type::Date))),
-            (Type::Table(vec![]), Type::Table(vec![])),
-            (Type::Record(vec![]), Type::Record(vec![])),
+            (Type::table(), Type::table()),
+            (Type::record(), Type::record()),
         ])
         .allow_variants_without_examples(true)
         .named(

crates/nu-command/src/conversions/into/duration.rs

@@ -17,9 +17,9 @@ impl Command for SubCommand {
                 (Type::Int, Type::Duration),
                 (Type::String, Type::Duration),
                 (Type::Duration, Type::Duration),
-                (Type::Table(vec![]), Type::Table(vec![])),
+                (Type::table(), Type::table()),
                 //todo: record<hour,minute,sign> | into duration -> Duration
-                //(Type::Record(vec![]), Type::Record(vec![])),
+                //(Type::record(), Type::record()),
             ])
             //.allow_variants_without_examples(true)
             .named(
@@ -203,9 +203,9 @@ fn string_to_duration(s: &str, span: Span) -> Result<i64, ShellError> {
         Type::Duration,
         |x| x,
     ) {
-        if let Expr::ValueWithUnit(value, unit) = expression.expr {
-            if let Expr::Int(x) = value.expr {
-                match unit.item {
+        if let Expr::ValueWithUnit(value) = expression.expr {
+            if let Expr::Int(x) = value.expr.expr {
+                match value.unit.item {
                     Unit::Nanosecond => return Ok(x),
                     Unit::Microsecond => return Ok(x * 1000),
                     Unit::Millisecond => return Ok(x * 1000 * 1000),

crates/nu-command/src/conversions/into/filesize.rs

@@ -18,8 +18,8 @@ impl Command for SubCommand {
                 (Type::Number, Type::Filesize),
                 (Type::String, Type::Filesize),
                 (Type::Filesize, Type::Filesize),
-                (Type::Table(vec![]), Type::Table(vec![])),
-                (Type::Record(vec![]), Type::Record(vec![])),
+                (Type::table(), Type::table()),
+                (Type::record(), Type::record()),
                 (
                     Type::List(Box::new(Type::Int)),
                     Type::List(Box::new(Type::Filesize)),

crates/nu-command/src/conversions/into/float.rs

@@ -16,8 +16,8 @@ impl Command for SubCommand {
                 (Type::String, Type::Float),
                 (Type::Bool, Type::Float),
                 (Type::Float, Type::Float),
-                (Type::Table(vec![]), Type::Table(vec![])),
-                (Type::Record(vec![]), Type::Record(vec![])),
+                (Type::table(), Type::table()),
+                (Type::record(), Type::record()),
                 (
                     Type::List(Box::new(Type::Any)),
                     Type::List(Box::new(Type::Float)),

crates/nu-command/src/conversions/into/glob.rs

@@ -27,8 +27,8 @@ impl Command for SubCommand {
                     Type::List(Box::new(Type::String)),
                     Type::List(Box::new(Type::Glob)),
                 ),
-                (Type::Table(vec![]), Type::Table(vec![])),
-                (Type::Record(vec![]), Type::Record(vec![])),
+                (Type::table(), Type::table()),
+                (Type::record(), Type::record()),
             ])
             .allow_variants_without_examples(true) // https://github.com/nushell/nushell/issues/7032
             .rest(

crates/nu-command/src/conversions/into/int.rs

@@ -36,8 +36,8 @@ impl Command for SubCommand {
                 (Type::Duration, Type::Int),
                 (Type::Filesize, Type::Int),
                 (Type::Binary, Type::Int),
-                (Type::Table(vec![]), Type::Table(vec![])),
-                (Type::Record(vec![]), Type::Record(vec![])),
+                (Type::table(), Type::table()),
+                (Type::record(), Type::record()),
                 (
                     Type::List(Box::new(Type::String)),
                     Type::List(Box::new(Type::Int)),

crates/nu-command/src/conversions/into/record.rs

@@ -13,11 +13,11 @@ impl Command for SubCommand {
     fn signature(&self) -> Signature {
         Signature::build("into record")
             .input_output_types(vec![
-                (Type::Date, Type::Record(vec![])),
-                (Type::Duration, Type::Record(vec![])),
-                (Type::List(Box::new(Type::Any)), Type::Record(vec![])),
-                (Type::Range, Type::Record(vec![])),
-                (Type::Record(vec![]), Type::Record(vec![])),
+                (Type::Date, Type::record()),
+                (Type::Duration, Type::record()),
+                (Type::List(Box::new(Type::Any)), Type::record()),
+                (Type::Range, Type::record()),
+                (Type::record(), Type::record()),
             ])
             .category(Category::Conversions)
     }

crates/nu-command/src/conversions/into/string.rs

@@ -40,8 +40,8 @@ impl Command for SubCommand {
                     Type::List(Box::new(Type::Any)),
                     Type::List(Box::new(Type::String)),
                 ),
-                (Type::Table(vec![]), Type::Table(vec![])),
-                (Type::Record(vec![]), Type::Record(vec![])),
+                (Type::table(), Type::table()),
+                (Type::record(), Type::record()),
             ])
             .allow_variants_without_examples(true) // https://github.com/nushell/nushell/issues/7032
             .rest(

crates/nu-command/src/conversions/into/value.rs

@@ -15,7 +15,7 @@ impl Command for IntoValue {
 
     fn signature(&self) -> Signature {
         Signature::build("into value")
-            .input_output_types(vec![(Type::Table(vec![]), Type::Table(vec![]))])
+            .input_output_types(vec![(Type::table(), Type::table())])
             .named(
                 "columns",
                 SyntaxShape::Table(vec![]),

crates/nu-command/src/database/commands/into_sqlite.rs

@@ -24,8 +24,8 @@ impl Command for IntoSqliteDb {
         Signature::build("into sqlite")
             .category(Category::Conversions)
             .input_output_types(vec![
-                (Type::Table(vec![]), Type::Nothing),
-                (Type::Record(vec![]), Type::Nothing),
+                (Type::table(), Type::Nothing),
+                (Type::record(), Type::Nothing),
             ])
             .allow_variants_without_examples(true)
             .required(

crates/nu-command/src/date/list_timezone.rs

@@ -11,7 +11,7 @@ impl Command for SubCommand {
 
     fn signature(&self) -> Signature {
         Signature::build("date list-timezone")
-            .input_output_types(vec![(Type::Nothing, Type::Table(vec![]))])
+            .input_output_types(vec![(Type::Nothing, Type::table())])
             .category(Category::Date)
     }
 

crates/nu-command/src/date/to_record.rs

@@ -13,8 +13,8 @@ impl Command for SubCommand {
     fn signature(&self) -> Signature {
         Signature::build("date to-record")
             .input_output_types(vec![
-                (Type::Date, Type::Record(vec![])),
-                (Type::String, Type::Record(vec![])),
+                (Type::Date, Type::record()),
+                (Type::String, Type::record()),
             ])
             .allow_variants_without_examples(true) // https://github.com/nushell/nushell/issues/7032
             .category(Category::Date)

crates/nu-command/src/date/to_table.rs

@@ -13,8 +13,8 @@ impl Command for SubCommand {
     fn signature(&self) -> Signature {
         Signature::build("date to-table")
             .input_output_types(vec![
-                (Type::Date, Type::Table(vec![])),
-                (Type::String, Type::Table(vec![])),
+                (Type::Date, Type::table()),
+                (Type::String, Type::table()),
             ])
             .allow_variants_without_examples(true) // https://github.com/nushell/nushell/issues/7032
             .category(Category::Date)

crates/nu-command/src/debug/ast.rs

@@ -16,7 +16,7 @@ impl Command for Ast {
 
     fn signature(&self) -> Signature {
         Signature::build("ast")
-            .input_output_types(vec![(Type::String, Type::Record(vec![]))])
+            .input_output_types(vec![(Type::String, Type::record())])
             .required(
                 "pipeline",
                 SyntaxShape::String,

crates/nu-command/src/debug/info.rs

@@ -31,7 +31,7 @@ impl Command for DebugInfo {
 
     fn signature(&self) -> nu_protocol::Signature {
         Signature::build("debug info")
-            .input_output_types(vec![(Type::Nothing, Type::Record(vec![]))])
+            .input_output_types(vec![(Type::Nothing, Type::record())])
             .category(Category::Debug)
     }
 

crates/nu-command/src/debug/metadata.rs

@@ -18,7 +18,7 @@ impl Command for Metadata {
 
     fn signature(&self) -> nu_protocol::Signature {
         Signature::build("metadata")
-            .input_output_types(vec![(Type::Any, Type::Record(vec![]))])
+            .input_output_types(vec![(Type::Any, Type::record())])
             .allow_variants_without_examples(true)
             .optional(
                 "expression",

crates/nu-command/src/debug/profile.rs

@@ -34,7 +34,7 @@ impl Command for DebugProfile {
                 "How many blocks/closures deep to step into (default 2)",
                 Some('m'),
             )
-            .input_output_types(vec![(Type::Any, Type::Table(vec![]))])
+            .input_output_types(vec![(Type::Any, Type::table())])
             .category(Category::Debug)
     }
 

crates/nu-command/src/debug/view_files.rs

@@ -20,12 +20,15 @@ impl Command for ViewFiles {
         Signature::build("view files")
             .input_output_types(vec![(
                 Type::Nothing,
-                Type::Table(vec![
-                    ("filename".into(), Type::String),
-                    ("start".into(), Type::Int),
-                    ("end".into(), Type::Int),
-                    ("size".into(), Type::Int),
-                ]),
+                Type::Table(
+                    [
+                        ("filename".into(), Type::String),
+                        ("start".into(), Type::Int),
+                        ("end".into(), Type::Int),
+                        ("size".into(), Type::Int),
+                    ]
+                    .into(),
+                ),
             )])
             .category(Category::Debug)
     }

crates/nu-command/src/env/load_env.rs

@@ -15,7 +15,7 @@ impl Command for LoadEnv {
     fn signature(&self) -> nu_protocol::Signature {
         Signature::build("load-env")
             .input_output_types(vec![
-                (Type::Record(vec![]), Type::Nothing),
+                (Type::record(), Type::Nothing),
                 (Type::Nothing, Type::Nothing),
             ])
             .allow_variants_without_examples(true)

crates/nu-command/src/filesystem/du.rs

@@ -33,7 +33,7 @@ impl Command for Du {
 
     fn signature(&self) -> Signature {
         Signature::build("du")
-            .input_output_types(vec![(Type::Nothing, Type::Table(vec![]))])
+            .input_output_types(vec![(Type::Nothing, Type::table())])
             .allow_variants_without_examples(true)
             .rest(
                 "path",

crates/nu-command/src/filesystem/ls.rs

@@ -45,7 +45,7 @@ impl Command for Ls {
 
     fn signature(&self) -> nu_protocol::Signature {
         Signature::build("ls")
-            .input_output_types(vec![(Type::Nothing, Type::Table(vec![]))])
+            .input_output_types(vec![(Type::Nothing, Type::table())])
             // LsGlobPattern is similar to string, it won't auto-expand
             // and we use it to track if the user input is quoted.
             .rest("pattern", SyntaxShape::OneOf(vec![SyntaxShape::GlobPattern, SyntaxShape::String]), "The glob pattern to use.")

crates/nu-command/src/filesystem/watch.rs

@@ -38,7 +38,7 @@ impl Command for Watch {
 
     fn signature(&self) -> nu_protocol::Signature {
         Signature::build("watch")
-        .input_output_types(vec![(Type::Nothing, Type::Table(vec![]))])
+        .input_output_types(vec![(Type::Nothing, Type::table())])
             .required("path", SyntaxShape::Filepath, "The path to watch. Can be a file or directory.")
             .required("closure",
             SyntaxShape::Closure(Some(vec![SyntaxShape::String, SyntaxShape::String, SyntaxShape::String])),

crates/nu-command/src/filters/columns.rs

@@ -11,8 +11,8 @@ impl Command for Columns {
     fn signature(&self) -> Signature {
         Signature::build(self.name())
             .input_output_types(vec![
-                (Type::Table(vec![]), Type::List(Box::new(Type::String))),
-                (Type::Record(vec![]), Type::List(Box::new(Type::String))),
+                (Type::table(), Type::List(Box::new(Type::String))),
+                (Type::record(), Type::List(Box::new(Type::String))),
             ])
             .category(Category::Filters)
     }

crates/nu-command/src/filters/drop/column.rs

@@ -13,8 +13,8 @@ impl Command for DropColumn {
     fn signature(&self) -> Signature {
         Signature::build(self.name())
             .input_output_types(vec![
-                (Type::Table(vec![]), Type::Table(vec![])),
-                (Type::Record(vec![]), Type::Record(vec![])),
+                (Type::table(), Type::table()),
+                (Type::record(), Type::record()),
             ])
             .optional(
                 "columns",

crates/nu-command/src/filters/drop/drop_.rs

@@ -11,7 +11,7 @@ impl Command for Drop {
     fn signature(&self) -> Signature {
         Signature::build("drop")
             .input_output_types(vec![
-                (Type::Table(vec![]), Type::Table(vec![])),
+                (Type::table(), Type::table()),
                 (
                     Type::List(Box::new(Type::Any)),
                     Type::List(Box::new(Type::Any)),

crates/nu-command/src/filters/each.rs

@@ -35,7 +35,7 @@ with 'transpose' first."#
                     Type::List(Box::new(Type::Any)),
                     Type::List(Box::new(Type::Any)),
                 ),
-                (Type::Table(vec![]), Type::List(Box::new(Type::Any))),
+                (Type::table(), Type::List(Box::new(Type::Any))),
                 (Type::Any, Type::Any),
             ])
             .required(

crates/nu-command/src/filters/enumerate.rs

@@ -18,7 +18,7 @@ impl Command for Enumerate {
 
     fn signature(&self) -> nu_protocol::Signature {
         Signature::build("enumerate")
-            .input_output_types(vec![(Type::Any, Type::Table(vec![]))])
+            .input_output_types(vec![(Type::Any, Type::table())])
             .category(Category::Filters)
     }
 

crates/nu-command/src/filters/flatten.rs

@@ -17,7 +17,7 @@ impl Command for Flatten {
                     Type::List(Box::new(Type::Any)),
                     Type::List(Box::new(Type::Any)),
                 ),
-                (Type::Record(vec![]), Type::Table(vec![])),
+                (Type::record(), Type::table()),
             ])
             .rest(
                 "rest",

crates/nu-command/src/filters/get.rs

@@ -27,8 +27,8 @@ If multiple cell paths are given, this will produce a list of values."#
                     Type::List(Box::new(Type::Any)),
                     Type::Any,
                 ),
-                (Type::Table(vec![]), Type::Any),
-                (Type::Record(vec![]), Type::Any),
+                (Type::table(), Type::Any),
+                (Type::record(), Type::Any),
             ])
             .required(
                 "cell_path",

crates/nu-command/src/filters/headers.rs

@@ -12,11 +12,11 @@ impl Command for Headers {
     fn signature(&self) -> Signature {
         Signature::build(self.name())
             .input_output_types(vec![
-                (Type::Table(vec![]), Type::Table(vec![])),
+                (Type::table(), Type::table()),
                 (
                     // Tables with missing values are List<Any>
                     Type::List(Box::new(Type::Any)),
-                    Type::Table(vec![]),
+                    Type::table(),
                 ),
             ])
             .category(Category::Filters)

crates/nu-command/src/filters/insert.rs

@@ -12,8 +12,8 @@ impl Command for Insert {
     fn signature(&self) -> Signature {
         Signature::build("insert")
             .input_output_types(vec![
-                (Type::Record(vec![]), Type::Record(vec![])),
-                (Type::Table(vec![]), Type::Table(vec![])),
+                (Type::record(), Type::record()),
+                (Type::table(), Type::table()),
                 (
                     Type::List(Box::new(Type::Any)),
                     Type::List(Box::new(Type::Any)),

crates/nu-command/src/filters/items.rs

@@ -12,7 +12,7 @@ impl Command for Items {
 
     fn signature(&self) -> Signature {
         Signature::build(self.name())
-            .input_output_types(vec![(Type::Record(vec![]), Type::Any)])
+            .input_output_types(vec![(Type::record(), Type::Any)])
             .required(
                 "closure",
                 SyntaxShape::Closure(Some(vec![SyntaxShape::Any, SyntaxShape::Any])),

crates/nu-command/src/filters/join.rs

@@ -46,7 +46,7 @@ impl Command for Join {
             .switch("left", "Left-outer join", Some('l'))
             .switch("right", "Right-outer join", Some('r'))
             .switch("outer", "Outer join", Some('o'))
-            .input_output_types(vec![(Type::Table(vec![]), Type::Table(vec![]))])
+            .input_output_types(vec![(Type::table(), Type::table())])
             .category(Category::Filters)
     }
 

crates/nu-command/src/filters/merge.rs

@@ -23,8 +23,8 @@ repeating this process with row 1, and so on."#
     fn signature(&self) -> nu_protocol::Signature {
         Signature::build("merge")
             .input_output_types(vec![
-                (Type::Record(vec![]), Type::Record(vec![])),
-                (Type::Table(vec![]), Type::Table(vec![])),
+                (Type::record(), Type::record()),
+                (Type::table(), Type::table()),
             ])
             .required(
                 "value",

crates/nu-command/src/filters/move_.rs

@@ -21,8 +21,8 @@ impl Command for Move {
     fn signature(&self) -> nu_protocol::Signature {
         Signature::build("move")
             .input_output_types(vec![
-                (Type::Record(vec![]), Type::Record(vec![])),
-                (Type::Table(vec![]), Type::Table(vec![])),
+                (Type::record(), Type::record()),
+                (Type::table(), Type::table()),
             ])
             .rest("columns", SyntaxShape::String, "The columns to move.")
             .named(

crates/nu-command/src/filters/par_each.rs

@@ -22,7 +22,7 @@ impl Command for ParEach {
                     Type::List(Box::new(Type::Any)),
                     Type::List(Box::new(Type::Any)),
                 ),
-                (Type::Table(vec![]), Type::List(Box::new(Type::Any))),
+                (Type::table(), Type::List(Box::new(Type::Any))),
                 (Type::Any, Type::Any),
             ])
             .named(

crates/nu-command/src/filters/reduce.rs

@@ -13,7 +13,7 @@ impl Command for Reduce {
         Signature::build("reduce")
             .input_output_types(vec![
                 (Type::List(Box::new(Type::Any)), Type::Any),
-                (Type::Table(vec![]), Type::Any),
+                (Type::table(), Type::Any),
                 (Type::Range, Type::Any),
             ])
             .named(

crates/nu-command/src/filters/reject.rs

@@ -13,8 +13,8 @@ impl Command for Reject {
     fn signature(&self) -> Signature {
         Signature::build("reject")
             .input_output_types(vec![
-                (Type::Record(vec![]), Type::Record(vec![])),
-                (Type::Table(vec![]), Type::Table(vec![])),
+                (Type::record(), Type::record()),
+                (Type::table(), Type::table()),
             ])
             .switch(
                 "ignore-errors",

crates/nu-command/src/filters/rename.rs

@@ -13,8 +13,8 @@ impl Command for Rename {
     fn signature(&self) -> Signature {
         Signature::build("rename")
             .input_output_types(vec![
-                (Type::Record(vec![]), Type::Record(vec![])),
-                (Type::Table(vec![]), Type::Table(vec![])),
+                (Type::record(), Type::record()),
+                (Type::table(), Type::table()),
             ])
             .named(
                 "column",

crates/nu-command/src/filters/select.rs

@@ -14,8 +14,8 @@ impl Command for Select {
     fn signature(&self) -> Signature {
         Signature::build("select")
             .input_output_types(vec![
-                (Type::Record(vec![]), Type::Record(vec![])),
-                (Type::Table(vec![]), Type::Table(vec![])),
+                (Type::record(), Type::record()),
+                (Type::table(), Type::table()),
                 (Type::List(Box::new(Type::Any)), Type::Any),
             ])
             .switch(

crates/nu-command/src/filters/skip/skip_.rs

@@ -11,7 +11,7 @@ impl Command for Skip {
     fn signature(&self) -> Signature {
         Signature::build(self.name())
             .input_output_types(vec![
-                (Type::Table(vec![]), Type::Table(vec![])),
+                (Type::table(), Type::table()),
                 (
                     Type::List(Box::new(Type::Any)),
                     Type::List(Box::new(Type::Any)),

crates/nu-command/src/filters/skip/skip_until.rs

@@ -12,7 +12,7 @@ impl Command for SkipUntil {
     fn signature(&self) -> Signature {
         Signature::build(self.name())
             .input_output_types(vec![
-                (Type::Table(vec![]), Type::Table(vec![])),
+                (Type::table(), Type::table()),
                 (
                     Type::List(Box::new(Type::Any)),
                     Type::List(Box::new(Type::Any)),

crates/nu-command/src/filters/skip/skip_while.rs

@@ -12,7 +12,7 @@ impl Command for SkipWhile {
     fn signature(&self) -> Signature {
         Signature::build(self.name())
             .input_output_types(vec![
-                (Type::Table(vec![]), Type::Table(vec![])),
+                (Type::table(), Type::table()),
                 (
                     Type::List(Box::new(Type::Any)),
                     Type::List(Box::new(Type::Any)),

crates/nu-command/src/filters/sort.rs

@@ -17,7 +17,7 @@ impl Command for Sort {
         .input_output_types(vec![(
             Type::List(Box::new(Type::Any)),
             Type::List(Box::new(Type::Any)),
-        ), (Type::Record(vec![]), Type::Record(vec![])),])
+        ), (Type::record(), Type::record()),])
     .switch("reverse", "Sort in reverse order", Some('r'))
             .switch(
                 "ignore-case",

crates/nu-command/src/filters/sort_by.rs

@@ -15,8 +15,8 @@ impl Command for SortBy {
                     Type::List(Box::new(Type::Any)),
                     Type::List(Box::new(Type::Any)),
                 ),
-                (Type::Record(vec![]), Type::Table(vec![])),
-                (Type::Table(vec![]), Type::Table(vec![])),
+                (Type::record(), Type::table()),
+                (Type::table(), Type::table()),
             ])
             .rest("columns", SyntaxShape::Any, "The column(s) to sort by.")
             .switch("reverse", "Sort in reverse order", Some('r'))

crates/nu-command/src/filters/split_by.rs

@@ -11,7 +11,7 @@ impl Command for SplitBy {
 
     fn signature(&self) -> Signature {
         Signature::build("split-by")
-            .input_output_types(vec![(Type::Record(vec![]), Type::Record(vec![]))])
+            .input_output_types(vec![(Type::record(), Type::record())])
             .optional("splitter", SyntaxShape::Any, "The splitter value to use.")
             .category(Category::Filters)
     }

crates/nu-command/src/filters/take/take_.rs

@@ -11,7 +11,7 @@ impl Command for Take {
     fn signature(&self) -> Signature {
         Signature::build("take")
             .input_output_types(vec![
-                (Type::Table(vec![]), Type::Table(vec![])),
+                (Type::table(), Type::table()),
                 (
                     Type::List(Box::new(Type::Any)),
                     Type::List(Box::new(Type::Any)),

crates/nu-command/src/filters/take/take_until.rs

@@ -12,7 +12,7 @@ impl Command for TakeUntil {
     fn signature(&self) -> Signature {
         Signature::build(self.name())
             .input_output_types(vec![
-                (Type::Table(vec![]), Type::Table(vec![])),
+                (Type::table(), Type::table()),
                 (
                     Type::List(Box::new(Type::Any)),
                     Type::List(Box::new(Type::Any)),

crates/nu-command/src/filters/take/take_while.rs

@@ -12,7 +12,7 @@ impl Command for TakeWhile {
     fn signature(&self) -> Signature {
         Signature::build(self.name())
             .input_output_types(vec![
-                (Type::Table(vec![]), Type::Table(vec![])),
+                (Type::table(), Type::table()),
                 (
                     Type::List(Box::new(Type::Any)),
                     Type::List(Box::new(Type::Any)),

crates/nu-command/src/filters/transpose.rs

@@ -20,8 +20,8 @@ impl Command for Transpose {
     fn signature(&self) -> Signature {
         Signature::build("transpose")
             .input_output_types(vec![
-                (Type::Table(vec![]), Type::Any),
-                (Type::Record(vec![]), Type::Table(vec![])),
+                (Type::table(), Type::Any),
+                (Type::record(), Type::table()),
             ])
             .switch(
                 "header-row",

crates/nu-command/src/filters/uniq_by.rs

@@ -12,7 +12,7 @@ impl Command for UniqBy {
     fn signature(&self) -> Signature {
         Signature::build("uniq-by")
             .input_output_types(vec![
-                (Type::Table(vec![]), Type::Table(vec![])),
+                (Type::table(), Type::table()),
                 (
                     Type::List(Box::new(Type::Any)),
                     Type::List(Box::new(Type::Any)),

crates/nu-command/src/filters/update.rs

@@ -12,8 +12,8 @@ impl Command for Update {
     fn signature(&self) -> Signature {
         Signature::build("update")
             .input_output_types(vec![
-                (Type::Record(vec![]), Type::Record(vec![])),
-                (Type::Table(vec![]), Type::Table(vec![])),
+                (Type::record(), Type::record()),
+                (Type::table(), Type::table()),
                 (
                     Type::List(Box::new(Type::Any)),
                     Type::List(Box::new(Type::Any)),

crates/nu-command/src/filters/upsert.rs

@@ -12,8 +12,8 @@ impl Command for Upsert {
     fn signature(&self) -> Signature {
         Signature::build("upsert")
             .input_output_types(vec![
-                (Type::Record(vec![]), Type::Record(vec![])),
-                (Type::Table(vec![]), Type::Table(vec![])),
+                (Type::record(), Type::record()),
+                (Type::table(), Type::table()),
                 (
                     Type::List(Box::new(Type::Any)),
                     Type::List(Box::new(Type::Any)),

crates/nu-command/src/filters/values.rs

@@ -12,8 +12,8 @@ impl Command for Values {
     fn signature(&self) -> Signature {
         Signature::build(self.name())
             .input_output_types(vec![
-                (Type::Record(vec![]), Type::List(Box::new(Type::Any))),
-                (Type::Table(vec![]), Type::List(Box::new(Type::Any))),
+                (Type::record(), Type::List(Box::new(Type::Any))),
+                (Type::table(), Type::List(Box::new(Type::Any))),
             ])
             .category(Category::Filters)
     }

crates/nu-command/src/filters/where_.rs

@@ -26,7 +26,7 @@ not supported."#
                     Type::List(Box::new(Type::Any)),
                     Type::List(Box::new(Type::Any)),
                 ),
-                (Type::Table(vec![]), Type::Table(vec![])),
+                (Type::table(), Type::table()),
                 (Type::Range, Type::Any),
             ])
             .required(

crates/nu-command/src/filters/wrap.rs

@@ -15,9 +15,9 @@ impl Command for Wrap {
     fn signature(&self) -> nu_protocol::Signature {
         Signature::build("wrap")
             .input_output_types(vec![
-                (Type::List(Box::new(Type::Any)), Type::Table(vec![])),
-                (Type::Range, Type::Table(vec![])),
-                (Type::Any, Type::Record(vec![])),
+                (Type::List(Box::new(Type::Any)), Type::table()),
+                (Type::Range, Type::table()),
+                (Type::Any, Type::record()),
             ])
             .required("name", SyntaxShape::String, "The name of the column.")
             .allow_variants_without_examples(true)

crates/nu-command/src/formats/from/csv.rs

@@ -11,7 +11,7 @@ impl Command for FromCsv {
 
     fn signature(&self) -> Signature {
         Signature::build("from csv")
-            .input_output_types(vec![(Type::String, Type::Table(vec![]))])
+            .input_output_types(vec![(Type::String, Type::table())])
             .named(
                 "separator",
                 SyntaxShape::String,

crates/nu-command/src/formats/from/ods.rs

@@ -14,7 +14,7 @@ impl Command for FromOds {
 
     fn signature(&self) -> Signature {
         Signature::build("from ods")
-            .input_output_types(vec![(Type::String, Type::Table(vec![]))])
+            .input_output_types(vec![(Type::String, Type::table())])
             .allow_variants_without_examples(true)
             .named(
                 "sheets",

crates/nu-command/src/formats/from/ssv.rs

@@ -13,7 +13,7 @@ impl Command for FromSsv {
 
     fn signature(&self) -> Signature {
         Signature::build("from ssv")
-            .input_output_types(vec![(Type::String, Type::Table(vec![]))])
+            .input_output_types(vec![(Type::String, Type::table())])
             .switch(
                 "noheaders",
                 "don't treat the first row as column names",

crates/nu-command/src/formats/from/toml.rs

@@ -11,7 +11,7 @@ impl Command for FromToml {
 
     fn signature(&self) -> Signature {
         Signature::build("from toml")
-            .input_output_types(vec![(Type::String, Type::Record(vec![]))])
+            .input_output_types(vec![(Type::String, Type::record())])
             .category(Category::Formats)
     }
 

crates/nu-command/src/formats/from/tsv.rs

@@ -11,7 +11,7 @@ impl Command for FromTsv {
 
     fn signature(&self) -> Signature {
         Signature::build("from tsv")
-            .input_output_types(vec![(Type::String, Type::Table(vec![]))])
+            .input_output_types(vec![(Type::String, Type::table())])
             .named(
                 "comment",
                 SyntaxShape::String,