livescript: merge eval and eval_ast, fix some regressions

 * map evaluation in step3
 * do in step 5

impls/livescript/env.ls

@@ -6,16 +6,6 @@ export class Env
     set: (symbol, ast) ->
         @data[symbol] = ast
 
-    find: (symbol) ->
-        if symbol of @data then @
-        else if @outer? then @outer.find symbol
-
     get: (symbol) ->
-        result = @try-get symbol
-        if not result
-        then throw new Error "'#{symbol}' not found"
-        else result
-
-    try-get: (symbol) ->
-        env = @find symbol
-        if env then env.data[symbol]
+        if symbol of @data then @data[symbol]
+        else if @outer? then @outer.get symbol

impls/livescript/step2_eval.ls

@@ -18,6 +18,9 @@ repl_env = do
         value: (a, b) -> {type: \int, value: parseInt(a.value / b.value)}
 
 eval_ast = (repl_env, {type, value}: ast) -->
+
+    # console.log "EVAL: #{pr_str ast}"
+
     switch type
     | \symbol =>
         result = repl_env[value]

impls/livescript/step3_env.ls

@@ -1,5 +1,5 @@
 readline = require './node_readline'
-{id, map, each} = require 'prelude-ls'
+{id, map, Obj, each} = require 'prelude-ls'
 {read_str} = require './reader'
 {pr_str} = require './printer'
 {Env} = require './env'
@@ -27,19 +27,25 @@ list-to-pairs = (list) ->
     [0 to (list.length - 2) by 2] \
         |> map (idx) -> [list[idx], list[idx+1]]
 
-
-eval_simple = (env, {type, value}: ast) ->
-    switch type
-    | \symbol => env.get value
-    | \list, \vector => do
-        type: type
-        value: value |> map eval_ast env
-    | otherwise => ast
+is-thruthy = ({type, value}) -> 
+    type != \const or value not in [\nil \false]
 
 
 eval_ast = (env, {type, value}: ast) -->
-    if type != \list then eval_simple env, ast
-    else if value.length == 0 then ast
+
+    dbgeval = env.get "DEBUG-EVAL"
+    if dbgeval and is-thruthy dbgeval then console.log "EVAL: #{pr_str ast}"
+
+    switch type
+    | \symbol => return (env.get value
+                         or throw new Error "'#{value}' not found")
+    | \list =>
+        # Proceed after this switch
+    | \vector => return {type: \vector, value: value |> map eval_ast env}
+    | \map => return {type: \map, value: value |> Obj.map eval_ast env}
+    | otherwise => return ast
+
+    if value.length == 0 then ast
     else if value[0].type == \symbol
         params = value[1 to]
         switch value[0].value

impls/livescript/step4_if_fn_do.ls

@@ -15,17 +15,21 @@ fmap-ast = (fn, {type, value}: ast) -->
     {type: type, value: fn value}
 
 
-eval_simple = (env, {type, value}: ast) ->
-    switch type
-    | \symbol => env.get value
-    | \list, \vector => ast |> fmap-ast map eval_ast env
-    | \map => ast |> fmap-ast Obj.map eval_ast env
-    | otherwise => ast
+eval_ast = (env, {type, value}: ast) -->
 
+    dbgeval = env.get "DEBUG-EVAL"
+    if dbgeval and is-thruthy dbgeval then console.log "EVAL: #{pr_str ast}"
 
-eval_ast = (env, {type, value}: ast) -->
-    if type != \list then eval_simple env, ast
-    else if value.length == 0 then ast
+    switch type
+    | \symbol => return (env.get value
+                         or throw new Error "'#{value}' not found")
+    | \list =>
+        # Proceed after this switch
+    | \vector => return (ast |> fmap-ast map eval_ast env)
+    | \map => return (ast |> fmap-ast Obj.map eval_ast env)
+    | otherwise => return ast
+
+    if value.length == 0 then ast
     else if value[0].type == \symbol
         params = value[1 to]
         switch value[0].value

impls/livescript/step5_tco.ls

@@ -21,20 +21,24 @@ fmap-ast = (fn, {type, value}: ast) -->
     {type: type, value: fn value}
 
 
-eval_simple = (env, {type, value}: ast) ->
-    switch type
-    | \symbol => env.get value
-    | \list, \vector => ast |> fmap-ast map eval_ast env
-    | \map => ast |> fmap-ast Obj.map eval_ast env
-    | otherwise => ast
+eval_ast = (env, {type, value}: ast) -->
+  loop
 
+    dbgeval = env.get "DEBUG-EVAL"
+    if dbgeval and is-thruthy dbgeval then console.log "EVAL: #{pr_str ast}"
 
-eval_ast = (env, {type, value}: ast) -->
-    loop
-        if type != \list
-            return eval_simple env, ast
-        else if value.length == 0
+    switch type
+    | \symbol => return (env.get value
+                         or throw new Error "'#{value}' not found")
+    | \list =>
+        # Proceed after this switch
+    | \vector => return (ast |> fmap-ast map eval_ast env)
+    | \map => return (ast |> fmap-ast Obj.map eval_ast env)
+    | otherwise => return ast
+
+    if value.length == 0
             return ast
+    else
 
         result = if value[0].type == \symbol
             params = value[1 to]
@@ -112,7 +116,7 @@ eval_do = (env, params) ->
 
     [...rest, last-param] = params
     rest |> each eval_ast env
-    tco env, last-param
+    defer-tco env, last-param
 
 
 eval_if = (env, params) ->

impls/livescript/step6_file.ls

@@ -22,20 +22,24 @@ fmap-ast = (fn, {type, value}: ast) -->
     {type: type, value: fn value}
 
 
-eval_simple = (env, {type, value}: ast) ->
-    switch type
-    | \symbol => env.get value
-    | \list, \vector => ast |> fmap-ast map eval_ast env
-    | \map => ast |> fmap-ast Obj.map eval_ast env
-    | otherwise => ast
+eval_ast = (env, {type, value}: ast) -->
+  loop
 
+    dbgeval = env.get "DEBUG-EVAL"
+    if dbgeval and is-thruthy dbgeval then console.log "EVAL: #{pr_str ast}"
 
-eval_ast = (env, {type, value}: ast) -->
-    loop
-        if type != \list
-            return eval_simple env, ast
-        else if value.length == 0
+    switch type
+    | \symbol => return (env.get value
+                         or throw new Error "'#{value}' not found")
+    | \list =>
+        # Proceed after this switch
+    | \vector => return (ast |> fmap-ast map eval_ast env)
+    | \map => return (ast |> fmap-ast Obj.map eval_ast env)
+    | otherwise => return ast
+
+    if value.length == 0
             return ast
+    else
 
         result = if value[0].type == \symbol
             params = value[1 to]

impls/livescript/step7_quote.ls

@@ -28,20 +28,24 @@ make-call = (name, params) -> make-list [make-symbol name] ++ params
 is-symbol = (ast, name) -> ast.type == \symbol and ast.value == name
 
 
-eval_simple = (env, {type, value}: ast) ->
-    switch type
-    | \symbol => env.get value
-    | \list, \vector => ast |> fmap-ast map eval_ast env
-    | \map => ast |> fmap-ast Obj.map eval_ast env
-    | otherwise => ast
+eval_ast = (env, {type, value}: ast) -->
+  loop
 
+    dbgeval = env.get "DEBUG-EVAL"
+    if dbgeval and is-thruthy dbgeval then console.log "EVAL: #{pr_str ast}"
 
-eval_ast = (env, {type, value}: ast) -->
-    loop
-        if type != \list
-            return eval_simple env, ast
-        else if value.length == 0
+    switch type
+    | \symbol => return (env.get value
+                         or throw new Error "'#{value}' not found")
+    | \list =>
+        # Proceed after this switch
+    | \vector => return (ast |> fmap-ast map eval_ast env)
+    | \map => return (ast |> fmap-ast Obj.map eval_ast env)
+    | otherwise => return ast
+
+    if value.length == 0
             return ast
+    else
 
         result = if value[0].type == \symbol
             params = value[1 to]
@@ -52,7 +56,6 @@ eval_ast = (env, {type, value}: ast) -->
             | 'if'         => eval_if env, params
             | 'fn*'        => eval_fn env, params
             | 'quote'      => eval_quote env, params
-            | 'quasiquoteexpand' => eval_quasiquoteexpand params
             | 'quasiquote' => eval_quasiquote env, params
             | otherwise    => eval_apply env, value
         else 

impls/livescript/step8_macros.ls

@@ -28,24 +28,24 @@ make-call = (name, params) -> make-list [make-symbol name] ++ params
 is-symbol = (ast, name) -> ast.type == \symbol and ast.value == name
 
 
-eval_simple = (env, {type, value}: ast) ->
-    switch type
-    | \symbol => env.get value
-    | \list, \vector => ast |> fmap-ast map eval_ast env
-    | \map => ast |> fmap-ast Obj.map eval_ast env
-    | otherwise => ast
-
+eval_ast = (env, {type, value}: ast) -->
+  loop
 
-eval_ast = (env, ast) -->
-    loop
-        if ast.type != \list
-            return eval_simple env, ast
+    dbgeval = env.get "DEBUG-EVAL"
+    if dbgeval and is-thruthy dbgeval then console.log "EVAL: #{pr_str ast}"
 
-        ast = macroexpand env, ast
-        if ast.type != \list
-            return eval_simple env, ast
-        else if ast.value.length == 0
+    switch type
+    | \symbol => return (env.get value
+                         or throw new Error "'#{value}' not found")
+    | \list =>
+        # Proceed after this switch
+    | \vector => return (ast |> fmap-ast map eval_ast env)
+    | \map => return (ast |> fmap-ast Obj.map eval_ast env)
+    | otherwise => return ast
+
+    if value.length == 0
             return ast
+    else
 
         result = if ast.value[0].type == \symbol
             params = ast.value[1 to]
@@ -56,16 +56,15 @@ eval_ast = (env, ast) -->
             | 'if'          => eval_if env, params
             | 'fn*'         => eval_fn env, params
             | 'quote'       => eval_quote env, params
-            | 'quasiquoteexpand' => eval_quasiquoteexpand params
             | 'quasiquote'  => eval_quasiquote env, params
             | 'defmacro!'   => eval_defmacro env, params
-            | 'macroexpand' => eval_macroexpand env, params
             | otherwise     => eval_apply env, ast.value
         else 
             eval_apply env, ast.value
 
         if result.type == \tco
-            {env, ast} = result
+            env = result.env
+            {type, value}: ast = result.ast
         else
             return result
 
@@ -198,10 +197,14 @@ eval_fn = (env, params) ->
 
 
 eval_apply = (env, list) ->
-    [fn, ...args] = list |> map eval_ast env
+    [first, ...raw_args] = list
+    fn = first |> eval_ast env
     if fn.type != \function
         runtime-error "#{fn.value} is not a function, got a #{fn.type}"
 
+    if fn.is_macro
+        return (defer-tco env, (unpack-tco (fn.value.apply env, raw_args)))
+    args = raw_args |> map eval_ast env
     fn.value.apply env, args
 
 
@@ -280,30 +283,6 @@ eval_defmacro = (env, params) ->
     env.set name.value, macro_fn
 
 
-get-macro-fn = (env, ast) ->
-    if ast.type == \list and
-            ast.value.length != 0 and
-            ast.value[0].type == \symbol
-        fn = env.try-get ast.value[0].value
-        if fn and fn.type == \function and fn.is_macro
-        then fn
-
-
-macroexpand = (env, ast) ->
-    loop # until ast is not a macro function call.
-        macro_fn = get-macro-fn env, ast
-        if not macro_fn then return ast
-        ast = unpack-tco <| macro_fn.value.apply env, ast.value[1 to]
-
-
-eval_macroexpand = (env, params) ->
-    if params.length != 1
-        runtime-error "'macroexpand' expected 1 parameter, 
-                       got #{params.length}"
-
-    macroexpand env, params[0]
-
-
 repl_env = new Env
 for symbol, value of ns
     repl_env.set symbol, value