Commit | Line | Data |
---|---|---|
d21ef941 | 1 | #! /usr/bin/env crystal run |
2 | ||
5185c56e | 3 | require "readline" |
d21ef941 | 4 | require "./reader" |
5 | require "./printer" | |
6 | require "./types" | |
7 | require "./env" | |
8 | require "./core" | |
9 | require "./error" | |
10 | ||
11 | # Note: | |
12 | # Employed downcase names because Crystal prohibits uppercase names for methods | |
13 | ||
97d0deb1 | 14 | module Mal |
15 | extend self | |
16 | ||
17 | def func_of(env, binds, body) | |
5185c56e | 18 | ->(args : Array(Mal::Type)) { |
97d0deb1 | 19 | new_env = Mal::Env.new(env, binds, args) |
20 | eval(body, new_env) | |
5185c56e | 21 | }.as(Mal::Func) |
97d0deb1 | 22 | end |
d21ef941 | 23 | |
97d0deb1 | 24 | def eval_ast(ast, env) |
5185c56e | 25 | return ast.map { |n| eval(n, env).as(Mal::Type) } if ast.is_a? Mal::List |
d21ef941 | 26 | |
97d0deb1 | 27 | val = ast.unwrap |
d21ef941 | 28 | |
97d0deb1 | 29 | Mal::Type.new case val |
30 | when Mal::Symbol | |
31 | if e = env.get(val.str) | |
32 | e | |
33 | else | |
34 | eval_error "'#{val.str}' not found" | |
35 | end | |
36 | when Mal::List | |
5185c56e | 37 | val.each_with_object(Mal::List.new) { |n, l| l << eval(n, env) } |
97d0deb1 | 38 | when Mal::Vector |
5185c56e | 39 | val.each_with_object(Mal::Vector.new) { |n, l| l << eval(n, env) } |
97d0deb1 | 40 | when Array(Mal::Type) |
5185c56e | 41 | val.map { |n| eval(n, env).as(Mal::Type) } |
97d0deb1 | 42 | when Mal::HashMap |
5185c56e | 43 | val.each { |k, v| val[k] = eval(v, env) } |
97d0deb1 | 44 | val |
d21ef941 | 45 | else |
97d0deb1 | 46 | val |
d21ef941 | 47 | end |
d21ef941 | 48 | end |
d21ef941 | 49 | |
97d0deb1 | 50 | def eval_invocation(list, env) |
51 | f = eval(list.first, env).unwrap | |
52 | case f | |
53 | when Mal::Closure | |
5185c56e | 54 | f.fn.call eval_ast(list[1..-1].each_with_object(Mal::List.new) { |i, l| l << i }, env) |
97d0deb1 | 55 | when Mal::Func |
5185c56e | 56 | f.call eval_ast(list[1..-1].each_with_object(Mal::List.new) { |i, l| l << i }, env) |
97d0deb1 | 57 | else |
58 | eval_error "expected function as the first argument" | |
59 | end | |
d21ef941 | 60 | end |
d21ef941 | 61 | |
97d0deb1 | 62 | def read(str) |
63 | read_str str | |
d21ef941 | 64 | end |
d21ef941 | 65 | |
97d0deb1 | 66 | macro invoke_list(l, env) |
67 | f = eval({{l}}.first, {{env}}).unwrap | |
68 | args = eval_ast({{l}}[1..-1].each_with_object(Mal::List.new){|i, l| l << i}, {{env}}) | |
69 | case f | |
70 | when Mal::Closure | |
71 | ast = f.ast | |
72 | {{env}} = Mal::Env.new(f.env, f.params, args) | |
73 | next # TCO | |
74 | when Mal::Func | |
75 | return f.call args | |
76 | else | |
77 | eval_error "expected function as the first argument" | |
78 | end | |
79 | end | |
d21ef941 | 80 | |
97d0deb1 | 81 | def eval(ast, env) |
82 | # 'next' in 'do...end' has a bug in crystal 0.7.1 | |
83 | # https://github.com/manastech/crystal/issues/659 | |
84 | while true | |
85 | list = ast.unwrap | |
d21ef941 | 86 | |
97d0deb1 | 87 | return eval_ast(ast, env) unless list.is_a? Mal::List |
88 | return gen_type Mal::List if list.empty? | |
d21ef941 | 89 | |
97d0deb1 | 90 | head = list.first.unwrap |
d21ef941 | 91 | |
97d0deb1 | 92 | unless head.is_a? Mal::Symbol |
93 | invoke_list(list, env) | |
94 | end | |
d21ef941 | 95 | |
97d0deb1 | 96 | return Mal::Type.new case head.str |
5185c56e OR |
97 | when "def!" |
98 | eval_error "wrong number of argument for 'def!'" unless list.size == 3 | |
99 | a1 = list[1].unwrap | |
100 | eval_error "1st argument of 'def!' must be symbol" unless a1.is_a? Mal::Symbol | |
101 | env.set(a1.str, eval(list[2], env)) | |
102 | when "let*" | |
103 | eval_error "wrong number of argument for 'def!'" unless list.size == 3 | |
104 | ||
105 | bindings = list[1].unwrap | |
106 | eval_error "1st argument of 'let*' must be list or vector" unless bindings.is_a? Array | |
107 | eval_error "size of binding list must be even" unless bindings.size.even? | |
108 | ||
109 | new_env = Mal::Env.new env | |
110 | bindings.each_slice(2) do |binding| | |
111 | key, value = binding | |
112 | name = key.unwrap | |
113 | eval_error "name of binding must be specified as symbol" unless name.is_a? Mal::Symbol | |
114 | new_env.set(name.str, eval(value, new_env)) | |
115 | end | |
116 | ||
117 | ast, env = list[2], new_env | |
118 | next # TCO | |
119 | when "do" | |
120 | if list.empty? | |
121 | ast = Mal::Type.new nil | |
122 | next | |
123 | end | |
124 | ||
125 | eval_ast(list[1..-2].each_with_object(Mal::List.new) { |i, l| l << i }, env) | |
126 | ast = list.last | |
127 | next # TCO | |
128 | when "if" | |
129 | ast = unless eval(list[1], env).unwrap | |
130 | list.size >= 4 ? list[3] : Mal::Type.new(nil) | |
d21ef941 | 131 | else |
5185c56e | 132 | list[2] |
d21ef941 | 133 | end |
5185c56e OR |
134 | next # TCO |
135 | when "fn*" | |
136 | params = list[1].unwrap | |
137 | unless params.is_a? Array | |
138 | eval_error "'fn*' parameters must be list" | |
139 | end | |
140 | Mal::Closure.new(list[2], params, env, func_of(env, params, list[2])) | |
141 | else | |
142 | invoke_list(list, env) | |
143 | end | |
97d0deb1 | 144 | end |
d21ef941 | 145 | end |
d21ef941 | 146 | |
97d0deb1 | 147 | def print(result) |
148 | pr_str(result, true) | |
149 | end | |
d21ef941 | 150 | |
97d0deb1 | 151 | def rep(str) |
5185c56e | 152 | print(eval(read(str), REPL_ENV)) |
97d0deb1 | 153 | end |
d21ef941 | 154 | end |
155 | ||
5185c56e OR |
156 | REPL_ENV = Mal::Env.new nil |
157 | Mal::NS.each { |k, v| REPL_ENV.set(k, Mal::Type.new(v)) } | |
158 | REPL_ENV.set("eval", Mal::Type.new ->(args : Array(Mal::Type)) { Mal.eval(args[0], REPL_ENV) }) | |
97d0deb1 | 159 | Mal.rep "(def! not (fn* (a) (if a false true)))" |
160 | Mal.rep "(def! load-file (fn* (f) (eval (read-string (str \"(do \" (slurp f) \")\")))))" | |
5185c56e OR |
161 | argv = Mal::List.new |
162 | REPL_ENV.set("*ARGV*", Mal::Type.new argv) | |
d21ef941 | 163 | |
164 | unless ARGV.empty? | |
165 | if ARGV.size > 1 | |
166 | ARGV[1..-1].each do |a| | |
5185c56e | 167 | argv << Mal::Type.new(a) |
d21ef941 | 168 | end |
169 | end | |
170 | ||
97d0deb1 | 171 | Mal.rep "(load-file \"#{ARGV[0]}\")" |
d21ef941 | 172 | exit |
173 | end | |
174 | ||
5185c56e | 175 | while line = Readline.readline("user> ", true) |
d21ef941 | 176 | begin |
97d0deb1 | 177 | puts Mal.rep(line) |
d21ef941 | 178 | rescue e |
179 | STDERR.puts e | |
180 | end | |
181 | end |