From 64ac81bf2024e2e563a7a5f4284dccb92c3b5c56 Mon Sep 17 00:00:00 2001
From: vendethiel <vendethiel@hotmail.fr>
Date: Wed, 30 Dec 2015 20:52:16 +0100
Subject: [PATCH] Start working on type ascriptions

---
 src/ast.ls     | 6 +++++-
 src/grammar.ls | 1 +
 src/lexer.ls   | 3 +++
 3 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/src/ast.ls b/src/ast.ls
index ca16730bf..5a03df23d 100644
--- a/src/ast.ls
+++ b/src/ast.ls
@@ -535,6 +535,8 @@ class exports.Var extends Atom
 
     maybe-key: -> Key(@value) <<< {@line}
 
+    set-type: (@type) -> this
+
     var-name: ::show
 
     compile: (o) -> sn(this, if @temp then o.scope.free @value else @value)
@@ -1915,7 +1917,9 @@ class exports.Fun extends Node
                     vr = v
                 else if df
                     assigns.push Assign vr, p.second, \=, p.op, true
-                names.push (scope.add vr.value, \arg, p), ', '
+                names.push (scope.add vr.value, \arg, p)
+                names.push " : #that" if vr.type?
+                names.push ', '
         if rest
             while splace-- then rest.unshift Arr!
             assigns.push Assign Arr(rest), Literal \arguments
diff --git a/src/grammar.ls b/src/grammar.ls
index dc4e8f2a0..d61c5976a 100644
--- a/src/grammar.ls
+++ b/src/grammar.ls
@@ -157,6 +157,7 @@ bnf =
     ArgList:
         o ''                                                -> []
         o 'Arg'                                             -> [$1]
+        o 'Arg ASCR ID'                                     -> [$1.set-type $3]
         o 'ArgList , Arg'                                   -> $1 ++ $3
         o 'ArgList OptComma NEWLINE Arg'                    -> $1 ++ $4
         o 'ArgList OptComma INDENT ArgList OptComma DEDENT' ditto
diff --git a/src/lexer.ls b/src/lexer.ls
index 02b515d02..0a8ef974d 100644
--- a/src/lexer.ls
+++ b/src/lexer.ls
@@ -652,6 +652,8 @@ exports <<<
             @adi!
             val = 'prototype'
             tag = 'ID'
+        case '@:'
+            tag = 'ASCR'
         case '=>'
             @unline!
             @fset 'for' false
@@ -1343,6 +1345,7 @@ SYMBOL = //
 | \([^\n\S]*\)                  # call
 | [!=]==?                       # strict equality, deep equals
 | !?\~=                         # fuzzy equality
+| @:                            # type ascription
 | @@?                           # this / constructor
 | <\[(?:[\s\S]*?\]>)?           # words
 | <<<<?                         # import