mirror of
https://github.com/kanaka/mal.git
synced 2024-11-14 20:27:35 +03:00
110 lines
3.0 KiB
CoffeeScript
110 lines
3.0 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
|
|
is_pair = (x) -> types._sequential_Q(x) && x.length > 0
|
|
|
|
quasiquote = (ast) ->
|
|
if !is_pair(ast) then [types._symbol('quote'), ast]
|
|
else if ast[0] != null && ast[0].name == 'unquote' then ast[1]
|
|
else if is_pair(ast[0]) && ast[0][0].name == 'splice-unquote'
|
|
[types._symbol('concat'), ast[0][1], quasiquote(ast[1..])]
|
|
else
|
|
[types._symbol('cons'), quasiquote(ast[0]), quasiquote(ast[1..])]
|
|
|
|
|
|
|
|
eval_ast = (ast, env) ->
|
|
if types._symbol_Q(ast) then env.get ast
|
|
else if types._list_Q(ast) then ast.map((a) -> EVAL(a, env))
|
|
else if types._vector_Q(ast)
|
|
types._vector(ast.map((a) -> EVAL(a, env))...)
|
|
else if types._hash_map_Q(ast)
|
|
new_hm = {}
|
|
new_hm[k] = EVAL(ast[k],env) for k,v of ast
|
|
new_hm
|
|
else ast
|
|
|
|
EVAL = (ast, env) ->
|
|
loop
|
|
#console.log "EVAL:", printer._pr_str ast
|
|
if !types._list_Q ast then return eval_ast ast, env
|
|
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 "quote"
|
|
return a1
|
|
when "quasiquote"
|
|
ast = quasiquote(a1)
|
|
when "do"
|
|
eval_ast(ast[1..-2], 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...] = eval_ast ast, 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
|
|
repl_env.set types._symbol('eval'), (ast) -> EVAL(ast, repl_env)
|
|
repl_env.set types._symbol('*ARGV*'), []
|
|
|
|
# core.mal: defined using the language itself
|
|
rep("(def! not (fn* (a) (if a false true)))");
|
|
rep("(def! load-file (fn* (f) (eval (read-string (str \"(do \" (slurp f) \")\")))))");
|
|
|
|
if process? && process.argv.length > 2
|
|
repl_env.set types._symbol('*ARGV*'), process.argv[3..]
|
|
rep('(load-file "' + process.argv[2] + '")')
|
|
process.exit 0
|
|
|
|
# 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? console.log exc.stack
|
|
else console.log exc
|
|
|
|
# vim: ts=2:sw=2
|