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|
readline = require "./node_readline.coffee"
types = require "./types.coffee"
reader = require "./reader.coffee"
printer = require "./printer.coffee"
# read
READ = (str) -> reader.read_str str
# eval
eval_ast = (ast, env) ->
if types._symbol_Q(ast) then env[ast.name]
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) ->
#console.log "EVAL:", printer._pr_str ast
if !types._list_Q ast then return eval_ast ast, env
# apply list
[f, args...] = eval_ast ast, env
f(args...)
# print
PRINT = (exp) -> printer._pr_str exp, true
# repl
repl_env = {}
rep = (str) -> PRINT(EVAL(READ(str), repl_env))
repl_env["+"] = (a,b) -> a+b
repl_env["-"] = (a,b) -> a-b
repl_env["*"] = (a,b) -> a*b
repl_env["/"] = (a,b) -> a/b
# 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 then console.log exc.stack
else console.log exc
# vim: ts=2:sw=2
|
