mirror of
https://github.com/kanaka/mal.git
synced 2024-09-19 01:28:26 +03:00
e6d41de4d5
Let `load-file` append a new line in case last line contains a comment. Also append `nil` so that the return value is predictible. Remove the existing explicit `nil` from existing sources. Adapt documentation and tests.
125 lines
2.9 KiB
Julia
Executable File
125 lines
2.9 KiB
Julia
Executable File
#!/usr/bin/env julia
|
|
|
|
push!(LOAD_PATH, pwd(), "/usr/share/julia/base")
|
|
import readline_mod
|
|
import reader
|
|
import printer
|
|
using env
|
|
import core
|
|
using types
|
|
|
|
# READ
|
|
function READ(str)
|
|
reader.read_str(str)
|
|
end
|
|
|
|
# EVAL
|
|
function eval_ast(ast, env)
|
|
if typeof(ast) == Symbol
|
|
env_get(env,ast)
|
|
elseif isa(ast, Array) || isa(ast, Tuple)
|
|
map((x) -> EVAL(x,env), ast)
|
|
elseif isa(ast, Dict)
|
|
[EVAL(x[1],env) => EVAL(x[2], env) for x=ast]
|
|
else
|
|
ast
|
|
end
|
|
end
|
|
|
|
function EVAL(ast, env)
|
|
while true
|
|
#println("EVAL: $(printer.pr_str(ast,true))")
|
|
if !isa(ast, Array) return eval_ast(ast, env) end
|
|
if isempty(ast) return ast end
|
|
|
|
# apply
|
|
if :def! == ast[1]
|
|
return env_set(env, ast[2], EVAL(ast[3], env))
|
|
elseif symbol("let*") == ast[1]
|
|
let_env = Env(env)
|
|
for i = 1:2:length(ast[2])
|
|
env_set(let_env, ast[2][i], EVAL(ast[2][i+1], let_env))
|
|
end
|
|
env = let_env
|
|
ast = ast[3]
|
|
# TCO loop
|
|
elseif :do == ast[1]
|
|
eval_ast(ast[2:end-1], env)
|
|
ast = ast[end]
|
|
# TCO loop
|
|
elseif :if == ast[1]
|
|
cond = EVAL(ast[2], env)
|
|
if cond === nothing || cond === false
|
|
if length(ast) >= 4
|
|
ast = ast[4]
|
|
# TCO loop
|
|
else
|
|
return nothing
|
|
end
|
|
else
|
|
ast = ast[3]
|
|
# TCO loop
|
|
end
|
|
elseif symbol("fn*") == ast[1]
|
|
return MalFunc(
|
|
(args...) -> EVAL(ast[3], Env(env, ast[2], Any[args...])),
|
|
ast[3], env, ast[2])
|
|
else
|
|
el = eval_ast(ast, env)
|
|
f, args = el[1], el[2:end]
|
|
if isa(f, MalFunc)
|
|
ast = f.ast
|
|
env = Env(f.env, f.params, args)
|
|
# TCO loop
|
|
else
|
|
return f(args...)
|
|
end
|
|
end
|
|
end
|
|
end
|
|
|
|
# PRINT
|
|
function PRINT(exp)
|
|
printer.pr_str(exp)
|
|
end
|
|
|
|
# REPL
|
|
repl_env = nothing
|
|
function REP(str)
|
|
return PRINT(EVAL(READ(str), repl_env))
|
|
end
|
|
|
|
# core.jl: defined using Julia
|
|
repl_env = Env(nothing, core.ns)
|
|
env_set(repl_env, :eval, (ast) -> EVAL(ast, repl_env))
|
|
env_set(repl_env, symbol("*ARGV*"), ARGS[2:end])
|
|
|
|
# core.mal: defined using the language itself
|
|
REP("(def! not (fn* (a) (if a false true)))")
|
|
REP("(def! load-file (fn* (f) (eval (read-string (str \"(do \" (slurp f) \"\nnil)\")))))")
|
|
|
|
if length(ARGS) > 0
|
|
REP("(load-file \"$(ARGS[1])\")")
|
|
exit(0)
|
|
end
|
|
|
|
while true
|
|
line = readline_mod.do_readline("user> ")
|
|
if line === nothing break end
|
|
try
|
|
println(REP(line))
|
|
catch e
|
|
if isa(e, ErrorException)
|
|
println("Error: $(e.msg)")
|
|
else
|
|
println("Error: $(string(e))")
|
|
end
|
|
# TODO: show at least part of stack
|
|
if !isa(e, StackOverflowError)
|
|
bt = catch_backtrace()
|
|
Base.show_backtrace(STDERR, bt)
|
|
end
|
|
println()
|
|
end
|
|
end
|