Commit | Line | Data |
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31690700 | 1 | if (typeof module !== 'undefined') { |
31b44161 | 2 | var types = require('./types'); |
31690700 | 3 | var readline = require('./node_readline'); |
31b44161 JM |
4 | var reader = require('./reader'); |
5 | var printer = require('./printer'); | |
6 | var Env = require('./env').Env; | |
7 | var core = require('./core'); | |
31690700 JM |
8 | } |
9 | ||
10 | // read | |
11 | function READ(str) { | |
12 | return reader.read_str(str); | |
13 | } | |
14 | ||
15 | // eval | |
16 | function is_pair(x) { | |
ea81a808 | 17 | return types._sequential_Q(x) && x.length > 0; |
31690700 JM |
18 | } |
19 | ||
20 | function quasiquote(ast) { | |
21 | if (!is_pair(ast)) { | |
ea81a808 | 22 | return [types._symbol("quote"), ast]; |
31690700 JM |
23 | } else if (ast[0].value === 'unquote') { |
24 | return ast[1]; | |
25 | } else if (is_pair(ast[0]) && ast[0][0].value === 'splice-unquote') { | |
8adb0827 JM |
26 | return [types._symbol("concat"), |
27 | ast[0][1], | |
28 | quasiquote(ast.slice(1))]; | |
31690700 | 29 | } else { |
8adb0827 JM |
30 | return [types._symbol("cons"), |
31 | quasiquote(ast[0]), | |
32 | quasiquote(ast.slice(1))]; | |
31690700 JM |
33 | } |
34 | } | |
35 | ||
36 | function is_macro_call(ast, env) { | |
ea81a808 JM |
37 | return types._list_Q(ast) && |
38 | types._symbol_Q(ast[0]) && | |
31690700 JM |
39 | env.find(ast[0].value) && |
40 | env.get(ast[0].value)._ismacro_; | |
41 | } | |
42 | ||
43 | function macroexpand(ast, env) { | |
44 | while (is_macro_call(ast, env)) { | |
45 | var mac = env.get(ast[0]); | |
46 | ast = mac.apply(mac, ast.slice(1)); | |
47 | } | |
48 | return ast; | |
49 | } | |
50 | ||
51 | function eval_ast(ast, env) { | |
ea81a808 | 52 | if (types._symbol_Q(ast)) { |
31690700 | 53 | return env.get(ast); |
ea81a808 | 54 | } else if (types._list_Q(ast)) { |
31690700 | 55 | return ast.map(function(a) { return EVAL(a, env); }); |
ea81a808 | 56 | } else if (types._vector_Q(ast)) { |
31690700 JM |
57 | var v = ast.map(function(a) { return EVAL(a, env); }); |
58 | v.__isvector__ = true; | |
59 | return v; | |
ea81a808 | 60 | } else if (types._hash_map_Q(ast)) { |
31690700 JM |
61 | var new_hm = {}; |
62 | for (k in ast) { | |
63 | new_hm[EVAL(k, env)] = EVAL(ast[k], env); | |
64 | } | |
65 | return new_hm; | |
66 | } else { | |
67 | return ast; | |
68 | } | |
69 | } | |
70 | ||
71 | function _EVAL(ast, env) { | |
72 | while (true) { | |
ea81a808 | 73 | |
31b44161 | 74 | //printer.println("EVAL:", types._pr_str(ast, true)); |
ea81a808 JM |
75 | if (!types._list_Q(ast)) { |
76 | return eval_ast(ast, env); | |
77 | } | |
78 | ||
79 | // apply list | |
80 | ast = macroexpand(ast, env); | |
81 | if (!types._list_Q(ast)) { return ast; } | |
82 | ||
83 | var a0 = ast[0], a1 = ast[1], a2 = ast[2], a3 = ast[3]; | |
84 | switch (a0.value) { | |
85 | case "def!": | |
86 | var res = EVAL(a2, env); | |
87 | return env.set(a1, res); | |
88 | case "let*": | |
89 | var let_env = new Env(env); | |
90 | for (var i=0; i < a1.length; i+=2) { | |
91 | let_env.set(a1[i].value, EVAL(a1[i+1], let_env)); | |
31690700 | 92 | } |
ea81a808 JM |
93 | return EVAL(a2, let_env); |
94 | case "quote": | |
95 | return a1; | |
96 | case "quasiquote": | |
97 | return EVAL(quasiquote(a1), env); | |
98 | case 'defmacro!': | |
99 | var func = EVAL(a2, env); | |
100 | func._ismacro_ = true; | |
101 | return env.set(a1, func); | |
102 | case 'macroexpand': | |
103 | return macroexpand(a1, env); | |
104 | case "do": | |
105 | eval_ast(ast.slice(1, -1), env); | |
106 | ast = ast[ast.length-1]; | |
107 | break; | |
108 | case "if": | |
109 | var cond = EVAL(a1, env); | |
110 | if (cond === null || cond === false) { | |
111 | ast = (typeof a3 !== "undefined") ? a3 : null; | |
112 | } else { | |
113 | ast = a2; | |
31690700 | 114 | } |
ea81a808 JM |
115 | break; |
116 | case "fn*": | |
117 | return types._function(EVAL, Env, a2, env, a1); | |
118 | default: | |
8adb0827 | 119 | var el = eval_ast(ast, env), f = el[0]; |
a34b0200 JM |
120 | if (f.__ast__) { |
121 | ast = f.__ast__; | |
122 | env = f.__gen_env__(el.slice(1)); | |
ea81a808 JM |
123 | } else { |
124 | return f.apply(f, el.slice(1)); | |
125 | } | |
126 | } | |
127 | ||
31690700 JM |
128 | } |
129 | } | |
130 | ||
131 | function EVAL(ast, env) { | |
132 | var result = _EVAL(ast, env); | |
133 | return (typeof result !== "undefined") ? result : null; | |
134 | } | |
135 | ||
136 | ||
137 | function PRINT(exp) { | |
ea81a808 | 138 | return printer._pr_str(exp, true); |
31690700 JM |
139 | } |
140 | ||
141 | // repl | |
ea81a808 | 142 | var repl_env = new Env(); |
31690700 JM |
143 | var rep = function(str) { return PRINT(EVAL(READ(str), repl_env)); }; |
144 | _ref = function (k,v) { repl_env.set(k, v); } | |
145 | ||
ea81a808 JM |
146 | // Import core functions |
147 | for (var n in core.ns) { repl_env.set(n, core.ns[n]); } | |
31690700 JM |
148 | |
149 | _ref('read-string', reader.read_str); | |
150 | _ref('eval', function(ast) { return EVAL(ast, repl_env); }); | |
151 | _ref('slurp', function(f) { | |
152 | return require('fs').readFileSync(f, 'utf-8'); | |
153 | }); | |
31690700 JM |
154 | |
155 | // Defined using the language itself | |
156 | rep("(def! not (fn* (a) (if a false true)))"); | |
1617910a | 157 | rep("(def! load-file (fn* (f) (eval (read-string (str \"(do \" (slurp f) \")\")))))"); |
31690700 JM |
158 | |
159 | if (typeof process !== 'undefined' && process.argv.length > 2) { | |
160 | for (var i=2; i < process.argv.length; i++) { | |
161 | rep('(load-file "' + process.argv[i] + '")'); | |
162 | } | |
163 | } else if (typeof require === 'undefined') { | |
164 | // Asynchronous browser mode | |
165 | readline.rlwrap(function(line) { return rep(line); }, | |
166 | function(exc) { | |
167 | if (exc instanceof reader.BlankException) { return; } | |
31b44161 JM |
168 | if (exc.stack) { printer.println(exc.stack); } |
169 | else { printer.println(exc); } | |
31690700 JM |
170 | }); |
171 | } else if (require.main === module) { | |
172 | // Synchronous node.js commandline mode | |
173 | while (true) { | |
174 | var line = readline.readline("user> "); | |
175 | if (line === null) { break; } | |
176 | try { | |
31b44161 | 177 | if (line) { printer.println(rep(line)); } |
31690700 JM |
178 | } catch (exc) { |
179 | if (exc instanceof reader.BlankException) { continue; } | |
31b44161 JM |
180 | if (exc.stack) { printer.println(exc.stack); } |
181 | else { printer.println(exc); } | |
31690700 JM |
182 | } |
183 | } | |
184 | } else { | |
185 | exports.rep = rep; | |
186 | } |