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mirror of https://github.com/kanaka/mal.git synced 2024-11-10 02:45:44 +03:00
mal/impls/coffee/step5_tco.coffee
Nicolas Boulenguez 033892777a Merge eval-ast and macro expansion into EVAL, add DEBUG-EVAL
See issue #587.
* Merge eval-ast and eval into a single conditional.
* Expand macros during the apply phase, removing lots of duplicate
  tests, and increasing the overall consistency by allowing the macro
  to be computed instead of referenced by name (`((defmacro! cond
  (...)))` is currently illegal for example).
* Print "EVAL: $ast" at the top of EVAL if DEBUG-EVAL exists in the
  MAL environment.
* Remove macroexpand and quasiquoteexpand special forms.
* Use pattern-matching style in process/step*.txt.

Unresolved issues:
c.2: unable to reproduce with gcc 11.12.0.
elm: the directory is unchanged.
groovy: sometimes fail, but not on each rebuild.
nasm: fails some new soft tests, but the issue is unreproducible when
  running the interpreter manually.
objpascal: unreproducible with fpc 3.2.2.
ocaml: unreproducible with 4.11.1.
perl6: unreproducible with rakudo 2021.09.

Unrelated changes:
Reduce diff betweens steps.
Prevent defmacro! from mutating functions: c forth logo miniMAL vb.
dart: fix recent errors and warnings
ocaml: remove metadata from symbols.

Improve the logo implementation.
Encapsulate all representation in types.lg and env.lg, unwrap numbers.
Replace some manual iterations with logo control structures.
Reduce the diff between steps.
Use native iteration in env_get and env_map
Rewrite the reader with less temporary strings.
Reduce the number of temporary lists (for example, reverse iteration
with butlast requires O(n^2) allocations).
It seems possible to remove a few exceptions: GC settings
(Dockerfile), NO_SELF_HOSTING (IMPLS.yml) and step5_EXCLUDES
(Makefile.impls) .
2024-08-05 11:40:49 -05:00

89 lines
2.3 KiB
CoffeeScript

readline = require "./node_readline.coffee"
types = require "./types.coffee"
reader = require "./reader.coffee"
printer = require "./printer.coffee"
Env = require("./env.coffee").Env
core = require("./core.coffee")
# read
READ = (str) -> reader.read_str str
# eval
EVAL = (ast, env) ->
loop
dbgenv = env.find("DEBUG-EVAL")
if dbgenv
dbgeval = dbgenv.get("DEBUG-EVAL")
if dbgeval != null and dbgeval != false
console.log "EVAL:", printer._pr_str ast
if types._symbol_Q(ast) then return env.get ast.name
else if types._list_Q(ast) then # exit this switch
else if types._vector_Q(ast)
return types._vector(ast.map((a) -> EVAL(a, env))...)
else if types._hash_map_Q(ast)
new_hm = {}
new_hm[k] = EVAL(v, env) for k,v of ast
return new_hm
else return ast
if ast.length == 0 then return ast
# apply list
[a0, a1, a2, a3] = ast
switch a0.name
when "def!"
return env.set(a1, EVAL(a2, env))
when "let*"
let_env = new Env(env)
for k,i in a1 when i %% 2 == 0
let_env.set(a1[i], EVAL(a1[i+1], let_env))
ast = a2
env = let_env
when "do"
ast[1..-2].map((a) -> EVAL(a, env))
ast = ast[ast.length-1]
when "if"
cond = EVAL(a1, env)
if cond == null or cond == false
if a3? then ast = a3 else return null
else
ast = a2
when "fn*"
return types._function(EVAL, a2, env, a1)
else
[f, args...] = ast.map((a) -> EVAL(a, env))
if types._function_Q(f)
ast = f.__ast__
env = f.__gen_env__(args)
else
return f(args...)
# print
PRINT = (exp) -> printer._pr_str exp, true
# repl
repl_env = new Env()
rep = (str) -> PRINT(EVAL(READ(str), repl_env))
# core.coffee: defined using CoffeeScript
repl_env.set types._symbol(k), v for k,v of core.ns
# core.mal: defined using the language itself
rep("(def! not (fn* (a) (if a false true)))");
# repl loop
while (line = readline.readline("user> ")) != null
continue if line == ""
try
console.log rep line
catch exc
continue if exc instanceof reader.BlankException
if exc.stack? and exc.stack.length > 2000
console.log exc.stack.slice(0,1000) + "\n ..." + exc.stack.slice(-1000)
else if exc.stack? then console.log exc.stack
else console.log exc
# vim: ts=2:sw=2