Improve colon sep

src/lex.rs

@@ -54,6 +54,13 @@ impl LexMode {
             _ => false,
         }
     }
+
+    pub fn special_contains(&self, b: u8) -> bool {
+        match self {
+            LexMode::Custom { ref special, .. } => special.contains(&b),
+            _ => false,
+        }
+    }
 }
 
 // A baseline token is terminated if it's not nested inside of a paired
@@ -67,7 +74,8 @@ fn is_item_terminator(block_level: &[BlockKind], c: u8, lex_mode: &LexMode) -> b
             || c == b'|'
             || c == b';'
             || c == b'#'
-            || lex_mode.whitespace_contains(c))
+            || lex_mode.whitespace_contains(c)
+            || lex_mode.special_contains(c))
 }
 
 // A special token is one that is a byte that stands alone as its own token. For example

src/parser.rs

@@ -999,7 +999,7 @@ impl ParserWorkingSet {
                                         desc: String::new(),
                                         long: String::from_utf8_lossy(contents).to_string(),
                                         short: None,
-                                        required: true,
+                                        required: false,
                                     }));
                                 } else {
                                     // Positional arg