diff --git a/src/build/app/mod.rs b/src/build/app/mod.rs
index a7b10d22..309681ee 100644
--- a/src/build/app/mod.rs
+++ b/src/build/app/mod.rs
@@ -22,6 +22,7 @@ use output::fmt::ColorWhen;
 use output::{Help, Usage};
 use parse::errors::Result as ClapResult;
 use parse::{ArgMatcher, ArgMatches, Parser};
+use mkeymap::{MKeyMap, KeyType};
 
 #[doc(hidden)]
 #[allow(dead_code)]
@@ -105,7 +106,7 @@ where
     #[doc(hidden)]
     pub g_settings: AppFlags,
     #[doc(hidden)]
-    pub args: Vec<Arg<'a, 'b>>,
+    pub args: MKeyMap,
     #[doc(hidden)]
     pub subcommands: Vec<App<'a, 'b>>,
     #[doc(hidden)]
@@ -637,6 +638,7 @@ impl<'a, 'b> App<'a, 'b> {
             None
         };
         let arg = a.into().help_heading(help_heading);
+        //TODO add push functionality to MKeyMap
         self.args.push(arg);
         self
     }
@@ -1439,12 +1441,13 @@ impl<'a, 'b> App<'a, 'b> {
         }
         // Perform expensive debug assertions
         debug_assert!({
-            for a in &self.args {
+            for a in self.args.values() {
                 self._arg_debug_asserts(a);
             }
             true
         });
-        for a in &mut self.args {
+        //TODO add .values_mut() for MKeyMap
+        for a in self.args.values_mut() {
             // Fill in the groups
             if let Some(ref grps) = a.groups {
                 for g in grps {
diff --git a/src/lib.rs b/src/lib.rs
index 2e39607f..7220d504 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -581,7 +581,11 @@ use std::result::Result as StdResult;
 
 #[macro_use]
 mod macros;
+<<<<<<< HEAD
 mod build;
+=======
+mod mkeymap;
+>>>>>>> WIP changing macros into MKeyMap calls
 mod completions;
 mod output;
 mod parse;
diff --git a/src/macros.rs b/src/macros.rs
index 45255919..dc19995d 100644
--- a/src/macros.rs
+++ b/src/macros.rs
@@ -1024,29 +1024,29 @@ macro_rules! find {
     }
 }
 
-macro_rules! find_by_long {
-    ($app:expr, $long:expr, $what:ident) => {{
-        $what!($app)
-            .filter(|a| a.long.is_some())
-            .find(|a| match_alias!(a, $long, a.long.unwrap()))
-    }};
-    ($app:expr, $long:expr) => {{
-        $app.args.iter()
-            .filter(|a| a.long.is_some())
-            .find(|a| match_alias!(a, $long, a.long.unwrap()))
-    }};
-}
+// macro_rules! find_by_long {
+//     ($app:expr, $long:expr, $what:ident) => {{
+//         $what!($app)
+//             .filter(|a| a.long.is_some())
+//             .find(|a| match_alias!(a, $long, a.long.unwrap()))
+//     }};
+//     ($app:expr, $long:expr) => {{
+//         $app.args.iter()
+//             .filter(|a| a.long.is_some())
+//             .find(|a| match_alias!(a, $long, a.long.unwrap()))
+//     }};
+// }
 
-macro_rules! find_by_short {
-    ($app:expr, $short:expr, $what:ident) => {{
-        $what!($app)
-            .find(|a| a.short == Some($short))
-    }};
-    ($app:expr, $short:expr) => {{
-        $app.args.iter()
-            .find(|a| a.short == Some($short))
-    }}
-}
+// macro_rules! find_by_short {
+//     ($app:expr, $short:expr, $what:ident) => {{
+//         $what!($app)
+//             .find(|a| a.short == Some($short))
+//     }};
+//     ($app:expr, $short:expr) => {{
+//         $app.args.iter()
+//             .find(|a| a.short == Some($short))
+//     }}
+// }
 
 macro_rules! find_subcmd_cloned {
     ($_self:expr, $sc:expr) => {{
@@ -1062,27 +1062,42 @@ macro_rules! find_subcmd {
     }};
 }
 
-macro_rules! shorts {
-    ($app:expr) => {{
-        _shorts_longs!($app, short)
-    }};
-}
+// macro_rules! shorts {
+//     ($app:expr) => {{
+//         _shorts_longs!($app, short)
+//     }};
+// }
 
+// macro_rules! longs {
+//     ($app:expr) => {{
+//         $app.args.iter()
+//             .filter(|a| a.long.is_some())
+//             .map(|a| a.long.unwrap())
+//             .chain($app.args.iter()
+//                 .filter(|a| a.aliases.is_some())
+//                 .flat_map(|a| a.aliases.as_ref().unwrap().iter().map(|als| als.0)))
+//     }};
+// }
+
+// macro_rules! _shorts_longs {
+//     ($app:expr, $what:ident) => {{
+//         $app.args.iter().filter_map(|a| a.$what)
+//     }};
+// }
+
+//TODO change into one macro (repeated structure)
 macro_rules! longs {
-    ($app:expr) => {{
-        $app.args.iter()
-            .filter(|a| a.long.is_some())
-            .map(|a| a.long.unwrap())
-            .chain($app.args.iter()
-                .filter(|a| a.aliases.is_some())
-                .flat_map(|a| a.aliases.as_ref().unwrap().iter().map(|als| als.0)))
-    }};
+    ($app:expr) => ({
+        use mkeymap::KeyType;
+        $app.args.keys().filter_map(|a| if let KeyType::Long(v) = a {Some(v)} else {None})
+    });
 }
 
-macro_rules! _shorts_longs {
-    ($app:expr, $what:ident) => {{
-        $app.args.iter().filter_map(|a| a.$what)
-    }};
+macro_rules! shorts {
+    ($app:expr) => ({
+        use mkeymap::KeyType;
+        $app.args.keys().filter_map(|a| if let KeyType::Short(v) = a {Some(v)} else {None})
+    })
 }
 
 macro_rules! _names {
@@ -1113,15 +1128,15 @@ macro_rules! sc_names {
     }};
 }
 
-macro_rules! match_alias {
-    ($a:expr, $to:expr, $what:expr) => {{
-        $what == $to ||
-        ($a.aliases.is_some() &&
-            $a.aliases
-            .as_ref()
-            .unwrap()
-            .iter()
-            .any(|alias| alias.0 == $to))
+// macro_rules! match_alias {
+//     ($a:expr, $to:expr, $what:expr) => {{
+//         $what == $to ||
+//         ($a.aliases.is_some() &&
+//             $a.aliases
+//             .as_ref()
+//             .unwrap()
+//             .iter()
+//             .any(|alias| alias.0 == $to))
 
-    }}
-}
+//     }}
+// }
diff --git a/src/mkeymap.rs b/src/mkeymap.rs
new file mode 100644
index 00000000..e9b5302d
--- /dev/null
+++ b/src/mkeymap.rs
@@ -0,0 +1,327 @@
+#![feature(nll)]
+
+use std::collections::hash_map;
+use std::collections::hash_map::DefaultHasher;
+use std::collections::{HashMap, HashSet};
+use std::ffi::OsStr;
+use std::hash::{Hash, Hasher};
+use std::slice;
+use build::Arg;
+// ! rustdoc
+
+#[derive(Default, PartialEq, Debug)]
+pub struct MKeyMap<'a, 'b>
+where
+    'a: 'b,
+{
+    keys: HashMap<KeyType<'a>, usize>,
+    value_index: Vec<Arg<'a, 'b>>,
+    values: HashMap<u64, HashSet<usize>>,
+}
+
+#[derive(Debug, PartialEq, Eq, Hash, Clone)]
+pub enum KeyType<'a> {
+    Short(char),
+    Long(&'a OsStr),
+    Position(usize),
+}
+
+impl<'a, 'b> MKeyMap<'a, 'b> {
+    pub fn new() -> Self {
+        MKeyMap::default()
+    }
+    //TODO ::from(x), ::with_capacity(n) etc
+    //? set theory ops?
+
+    pub fn insert(&mut self, key: KeyType<'a>, value: Arg<'a, 'b>) -> usize {
+        let index = self.push(value);
+        self.keys.insert(key, index);
+        index
+    }
+
+    pub fn push(&mut self, value: Arg<'a, 'b>) -> usize {
+        let index;
+        let mut hasher = DefaultHasher::new();
+
+        value.hash(&mut hasher);
+
+        let hash = hasher.finish();
+
+        if let Some((idx, _)) = self.values.get(&hash).and_then(|ids| {
+            ids.iter()
+                .map(|&x| (x, &self.value_index[x]))
+                .find(|(_i, x)| x == &&value)
+        }) {
+            index = idx;
+        } else {
+            self.value_index.push(value);
+            index = self.value_index.len() - 1;
+            self.values
+                .entry(hash)
+                .and_modify(|x| {
+                    x.insert(index);
+                })
+                .or_insert({
+                    let mut set = HashSet::new();
+                    set.insert(index);
+                    set
+                });
+        }
+    }
+    //TODO ::push_many([x, y])
+
+    pub fn insert_key(&mut self, key: KeyType<'a>, index: usize) {
+        if index >= self.values.len() {
+            panic!("Index out of bounds");
+        }
+
+        self.keys.insert(key, index);
+    }
+    //TODO ::insert_keyset([Long, Key2])
+
+    pub fn insert_key_by_name(&mut self, key: KeyType<'a>, name: &str) {
+        let index = self
+            .value_index
+            .iter()
+            .position(|x| x.name == name)
+            .expect("No such name found");
+
+        self.keys.insert(key, index);
+    }
+
+    pub fn get(&self, key: KeyType<'a>) -> &Arg<'a, 'b> {
+        self.keys
+            .get(&key)
+            .and_then(|&idx| self.value_index.get(idx))
+            .expect(&format!("No entry for the key: {:?}", key))
+    }
+    //TODO ::get_first([KeyA, KeyB])
+
+    pub fn get_mut(&mut self, key: KeyType<'a>) -> &mut Arg<'a, 'b> {
+        let idx = *self
+            .keys
+            .get(&key)
+            .expect(&format!("No entry for the key: {:?}", key));
+
+        self.value_index.get_mut(idx).unwrap()
+    }
+
+    pub fn is_empty(&self) -> bool {
+        self.keys.is_empty() && self.values.is_empty()
+    }
+
+    pub fn remove(&mut self, key: KeyType) -> Option<Arg> {
+        unimplemented!()
+    }
+    //TODO ::remove_many([KeyA, KeyB])
+    //? probably shouldn't add a possibility for removal?
+    //? or remove by replacement by some dummy object, so the order is preserved
+
+    pub fn remove_key(&mut self, key: KeyType) {
+        unimplemented!()
+    }
+    //TODO ::remove_keys([KeyA, KeyB])
+
+    pub fn keys(&'a self) -> Keys<'a, usize> {
+        Keys {
+            iter: self.keys.keys(),
+        }
+    }
+
+    pub fn values(&'a self) -> Values<'a, Arg> {
+        Values {
+            iter: self.value_index.iter(),
+        }
+    }
+
+    pub fn values_mut(&'a mut self) -> ValuesMut<'a, Arg> {
+        ValuesMut {
+            iter: self.value_index.iter_mut(),
+        }
+    }
+}
+
+pub struct Keys<'a, V: 'a> {
+    iter: hash_map::Keys<'a, KeyType<'a>, V>,
+}
+
+impl<'a, V> Iterator for Keys<'a, V> {
+    type Item = &'a KeyType<'a>;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        self.iter.next()
+    }
+}
+
+pub struct Values<'a, V: 'a> {
+    iter: slice::Iter<'a, V>,
+}
+
+impl<'a, V> Iterator for Values<'a, V> {
+    type Item = &'a V;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        self.iter.next()
+    }
+}
+
+pub struct ValuesMut<'a, V: 'a> {
+    iter: slice::IterMut<'a, V>,
+}
+
+impl<'a, V> Iterator for ValuesMut<'a, V> {
+    type Item = &'a V;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        self.iter.next()
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use std::ffi::OsStr;
+    use self::KeyType::*;
+
+    #[test]
+    fn get_some_value() {
+        let mut map: MKeyMap = MKeyMap::new();
+
+        {
+            map.insert(Long(&OsStr::new("One")), Arg::with_name("Value1"));
+        }
+
+        assert_eq!(
+            map.get(Long(&OsStr::new("One"))),
+            &Arg::with_name("Value1")
+        );
+    }
+
+    #[test]
+    #[should_panic]
+    fn get_none_value() {
+        let mut map: MKeyMap = MKeyMap::new();
+
+        map.insert(Long(&OsStr::new("One")), Arg::with_name("Value1"));
+        map.get(Long(&OsStr::new("Two")));
+    }
+
+    //    #[test]
+    //    fn insert_delete_value() {
+    //        let mut map = MKeyMap::new();
+    //        map.insert("One", clap::Arg::with_name("Value1"));
+    //        assert_eq!(map.remove("One"), Some(clap::Arg::with_name("Value1")));
+    //        assert!(map.is_empty());
+    //    }
+
+    #[test]
+    fn insert_duplicate_key() {
+        let mut map: MKeyMap = MKeyMap::new();
+
+        map.insert(Long(&OsStr::new("One")), Arg::with_name("Value1"));
+
+        assert_eq!(
+            map.insert(Long(&OsStr::new("One")), Arg::with_name("Value2")),
+            1
+        );
+    }
+
+    #[test]
+    fn insert_duplicate_value() {
+        let mut map: MKeyMap = MKeyMap::new();
+
+        map.insert(Long(&OsStr::new("One")), Arg::with_name("Value1"));
+
+        let orig_len = map.values.len();
+
+        map.insert(Long(&OsStr::new("Two")), Arg::with_name("Value1"));
+
+        assert_eq!(map.values.len(), orig_len);
+        assert_eq!(
+            map.get(Long(&OsStr::new("One"))),
+            map.get(Long(&OsStr::new("Two")))
+        );
+    }
+
+    //    #[test]
+    //    fn insert_delete_none() {
+    //        let mut map = MKeyMap::new();
+    //        map.insert("One", clap::Arg::with_name("Value1"));
+    //        assert_eq!(map.remove("Two"), None);
+    //        assert!(!map.is_empty());
+    //        assert_eq!(map.get("One"), Some(clap::Arg::with_name("Value1")));
+    //    }
+
+    #[test]
+    fn insert_multiple_keys() {
+        let mut map: MKeyMap = MKeyMap::new();
+        let index = map.insert(Long(&OsStr::new("One")), Arg::with_name("Value1"));
+
+        map.insert_key(Long(&OsStr::new("Two")), index);
+
+        assert_eq!(
+            map.get(Long(&OsStr::new("One"))),
+            map.get(Long(&OsStr::new("Two")))
+        );
+        assert_eq!(map.values.len(), 1);
+    }
+    
+    #[test]
+    fn insert_by_name() {
+        let mut map: MKeyMap = MKeyMap::new();
+        let index = map.insert(Long(&OsStr::new("One")), Arg::with_name("Value1"));
+
+        map.insert_key_by_name(Long(&OsStr::new("Two")), "Value1");
+
+        assert_eq!(
+            map.get(Long(&OsStr::new("One"))),
+            map.get(Long(&OsStr::new("Two")))
+        );
+        assert_eq!(map.values.len(), 1);
+    }
+
+    #[test]
+    fn get_mutable(){
+        let mut map: MKeyMap = MKeyMap::new();
+
+        map.insert(Long(&OsStr::new("One")), Arg::with_name("Value1"));
+
+        assert_eq!(
+            map.get_mut(Long(&OsStr::new("One"))),
+            &mut Arg::with_name("Value1")
+        );        
+    }
+
+    #[test]
+    fn remove_key() {
+        let mut map: MKeyMap = MKeyMap::new();
+        let index = map.insert(Long(&OsStr::new("One")), Arg::with_name("Value1"));
+
+        map.insert_key(Long(&OsStr::new("Two")), index);
+        map.remove_key(Long(&OsStr::new("One")));
+
+        assert_eq!(map.keys.len(), 1);
+        assert_eq!(map.values.len(), 1);
+    }
+
+    #[test]
+    fn iter_keys() {
+        let mut map: MKeyMap = MKeyMap::new();
+
+        map.insert(Long(&OsStr::new("One")), Arg::with_name("Value1"));
+        map.insert(Long(&OsStr::new("Two")), Arg::with_name("Value2"));
+        map.insert(Position(1), Arg::with_name("Value1"));
+
+        let iter = map.keys().cloned();
+        let mut ground_truth = HashSet::new();
+
+        ground_truth.insert(Long(&OsStr::new("One")));
+        ground_truth.insert(Long(&OsStr::new("Two")));
+        ground_truth.insert(Position(1));
+
+        assert_eq!(
+            ground_truth.symmetric_difference(&iter.collect()).count(),
+            0
+        );
+    }
+}
diff --git a/src/parse/parser.rs b/src/parse/parser.rs
index 33cda764..60dfb329 100644
--- a/src/parse/parser.rs
+++ b/src/parse/parser.rs
@@ -38,6 +38,9 @@ use parse::{ArgMatcher, SubCommand};
 use util::OsStrExt2;
 use INVALID_UTF8;
 use INTERNAL_ERROR_MSG;
+use parse::features::suggestions;
+use output::Usage;
+use mkeymap::KeyType;
 
 #[derive(Debug, PartialEq, Copy, Clone)]
 #[doc(hidden)]
@@ -303,7 +306,22 @@ where
     pub(crate) fn _build(&mut self) {
         debugln!("Parser::_build;");
 
-        for a in &mut self.app.args {
+        for (i, a) in self.app.args.values_mut().enumerate() {
+            if let Some(index) = a.index {
+                self.app.args.insert_key(KeyType::Positional(index), i);
+            } else {
+                if let Some(c) = a.short {
+                    self.app.args.insert_key(KeyType::Short(c), i);
+                }
+                if let Some(l) = a.long {
+                    self.app.args.insert_key(KeyType::Long(&OsStr::new(l)), i);
+                }
+                if let Some(v) = a.aliases {
+                    for (item, _) in &v {
+                        self.app.args.insert_key(KeyType::Long(&OsStr::new(item)), i);
+                    }
+                }
+            }
             // Add conditional requirements
             if let Some(ref r_ifs) = a.r_ifs {
                 for &(arg, val) in r_ifs {
@@ -1012,8 +1030,9 @@ where
             sdebugln!("No");
             full_arg.trim_left_matches(b'-')
         };
-
-        if let Some(opt) = find_by_long!(self.app, arg, opts) {
+// opts?? Should probably now check once, then check whether it's opt or flag, or sth else
+        if let Some(opt) = self.app.args.get(KeyType::Long(arg))
+        {
             debugln!(
                 "Parser::parse_long_arg: Found valid opt '{}'",
                 opt.to_string()
@@ -1025,7 +1044,8 @@ where
             }
 
             return Ok(ret);
-        } else if let Some(flag) = find_by_long!(self.app, arg, flags) {
+//flags??
+        } else if let Some(flag) = self.app.args.get(KeyType::Long(arg)) {
             debugln!(
                 "Parser::parse_long_arg: Found valid flag '{}'",
                 flag.to_string()
@@ -1092,7 +1112,7 @@ where
             // concatenated value: -oval
             // Option: -o
             // Value: val
-            if let Some(opt) = find_by_short!(self.app, c, opts) {
+            if let Some(opt) = self.app.args.get(KeyType::Short(c)) {
                 debugln!("Parser::parse_short_arg:iter:{}: Found valid opt", c);
                 self.app.settings.set(AS::ValidArgFound);
                 // Check for trailing concatenated value
@@ -1124,7 +1144,7 @@ where
                 }
 
                 return Ok(ret);
-            } else if let Some(flag) = find_by_short!(self.app, c, flags) {
+            } else if let Some(flag) = self.app.args.get(KeyType::Short(c)) {
                 debugln!("Parser::parse_short_arg:iter:{}: Found valid flag", c);
                 self.app.settings.set(AS::ValidArgFound);
                 // Only flags can be help or version
@@ -1510,11 +1530,11 @@ where
 
         // Add the arg to the matches to build a proper usage string
         if let Some(name) = suffix.1 {
-            if let Some(opt) = find_by_long!(self.app, name) {
+            if let Some(opt) = self.app.args.get(KeyType::Long(name)) {
                 self.groups_for_arg(&*opt.name)
                     .and_then(|grps| Some(matcher.inc_occurrences_of(&*grps)));
                 matcher.insert(&*opt.name);
-            } else if let Some(flg) = find_by_long!(self.app, name) {
+            } else if let Some(flg) = self.app.args.get(KeyType::Long(name)) {
                 self.groups_for_arg(&*flg.name)
                     .and_then(|grps| Some(matcher.inc_occurrences_of(&*grps)));
                 matcher.insert(&*flg.name);