io: merge macroexpand into eval

kanaka · Oct 29, 2024 · dfc67ee · dfc67ee
1 parent 78b0d7a
commit dfc67ee
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Showing 3 changed files with 21 additions and 69 deletions.
diff --git a/impls/io/step8_macros.io b/impls/io/step8_macros.io
@@ -20,23 +20,6 @@ quasiquote := method(ast,
                          qq_foldr(ast)),
         ast))
 
-isMacroCall := method(ast, env,
-    if(ast type != "MalList", return false)
-    a0 := ast first
-    if(a0 type != "MalSymbol", return false)
-    if(env find(a0) isNil, return false)
-    f := env get(a0)
-    (f type == "MalFunc") and (f isMacro)
-)
-
-macroexpand := method(ast, env,
-    while(isMacroCall(ast, env),
-        macro := env get(ast at(0))
-        ast = macro blk call(ast rest)
-    )
-    ast
-)
-
 eval_ast := method(ast, env,
    (ast type) switch(
        "MalSymbol", env get(ast),
@@ -62,9 +45,6 @@ EVAL := method(ast, env,
             ("EVAL: " .. PRINT(ast)) println)
 
         if(ast type != "MalList", return(eval_ast(ast, env)))
-
-        ast = macroexpand(ast, env)
-        if(ast type != "MalList", return(eval_ast(ast, env)))
         if(ast isEmpty, return ast)
 
         if(ast at(0) type == "MalSymbol",
@@ -103,13 +83,17 @@ EVAL := method(ast, env,
         )
 
         // Apply
-        el := eval_ast(ast, env)
-        f := el at(0)
-        args := el rest
+        f := EVAL(ast at(0), env)
+        raw_args := ast rest
         f type switch(
             "Block",
+                args := eval_ast(raw_args, env)
                 return(f call(args)),
             "MalFunc",
+                if(f isMacro,
+                    ast = f blk call(raw_args)
+                    continue) // TCO
+                args := eval_ast(raw_args, env)
                 ast = f ast
                 env = Env with(f env, f params, args)
                 continue, // TCO

diff --git a/impls/io/step9_try.io b/impls/io/step9_try.io
@@ -20,23 +20,6 @@ quasiquote := method(ast,
                          qq_foldr(ast)),
         ast))
 
-isMacroCall := method(ast, env,
-    if(ast type != "MalList", return false)
-    a0 := ast first
-    if(a0 type != "MalSymbol", return false)
-    if(env find(a0) isNil, return false)
-    f := env get(a0)
-    (f type == "MalFunc") and (f isMacro)
-)
-
-macroexpand := method(ast, env,
-    while(isMacroCall(ast, env),
-        macro := env get(ast at(0))
-        ast = macro blk call(ast rest)
-    )
-    ast
-)
-
 eval_ast := method(ast, env,
    (ast type) switch(
        "MalSymbol", env get(ast),
@@ -62,9 +45,6 @@ EVAL := method(ast, env,
             ("EVAL: " .. PRINT(ast)) println)
 
         if(ast type != "MalList", return(eval_ast(ast, env)))
-
-        ast = macroexpand(ast, env)
-        if(ast type != "MalList", return(eval_ast(ast, env)))
         if(ast isEmpty, return ast)
 
         if(ast at(0) type == "MalSymbol",
@@ -114,13 +94,17 @@ EVAL := method(ast, env,
         )
 
         // Apply
-        el := eval_ast(ast, env)
-        f := el at(0)
-        args := el rest
+        f := EVAL(ast at(0), env)
+        raw_args := ast rest
         f type switch(
             "Block",
+                args := eval_ast(raw_args, env)
                 return(f call(args)),
             "MalFunc",
+                if(f isMacro,
+                    ast = f blk call(raw_args)
+                    continue) // TCO
+                args := eval_ast(raw_args, env)
                 ast = f ast
                 env = Env with(f env, f params, args)
                 continue, // TCO

diff --git a/impls/io/stepA_mal.io b/impls/io/stepA_mal.io
@@ -20,23 +20,6 @@ quasiquote := method(ast,
                          qq_foldr(ast)),
         ast))
 
-isMacroCall := method(ast, env,
-    if(ast type != "MalList", return false)
-    a0 := ast first
-    if(a0 type != "MalSymbol", return false)
-    if(env find(a0) isNil, return false)
-    f := env get(a0)
-    (f type == "MalFunc") and (f isMacro)
-)
-
-macroexpand := method(ast, env,
-    while(isMacroCall(ast, env),
-        macro := env get(ast at(0))
-        ast = macro blk call(ast rest)
-    )
-    ast
-)
-
 eval_ast := method(ast, env,
    (ast type) switch(
        "MalSymbol", env get(ast),
@@ -62,9 +45,6 @@ EVAL := method(ast, env,
             ("EVAL: " .. PRINT(ast)) println)
 
         if(ast type != "MalList", return(eval_ast(ast, env)))
-
-        ast = macroexpand(ast, env)
-        if(ast type != "MalList", return(eval_ast(ast, env)))
         if(ast isEmpty, return ast)
 
         if(ast at(0) type == "MalSymbol",
@@ -114,13 +94,17 @@ EVAL := method(ast, env,
         )
 
         // Apply
-        el := eval_ast(ast, env)
-        f := el at(0)
-        args := el rest
+        f := EVAL(ast at(0), env)
+        raw_args := ast rest
         f type switch(
             "Block",
+                args := eval_ast(raw_args, env)
                 return(f call(args)),
             "MalFunc",
+                if(f isMacro,
+                    ast = f blk call(raw_args)
+                    continue) // TCO
+                args := eval_ast(raw_args, env)
                 ast = f ast
                 env = Env with(f env, f params, args)
                 continue, // TCO