Commit | Line | Data |
---|---|---|
c4033aab JM |
1 | function step8_macros(varargin), main(varargin), end |
2 | ||
3 | % read | |
4 | function ret = READ(str) | |
5 | ret = reader.read_str(str); | |
6 | end | |
7 | ||
8 | % eval | |
9 | function ret = is_pair(ast) | |
6a572dff | 10 | ret = types.sequential_Q(ast) && length(ast) > 0; |
c4033aab JM |
11 | end |
12 | ||
13 | function ret = quasiquote(ast) | |
14 | if ~is_pair(ast) | |
6a572dff JM |
15 | ret = types.List(types.Symbol('quote'), ast); |
16 | elseif isa(ast.get(1),'types.Symbol') && ... | |
17 | strcmp(ast.get(1).name, 'unquote') | |
18 | ret = ast.get(2); | |
19 | elseif is_pair(ast.get(1)) && ... | |
20 | isa(ast.get(1).get(1),'types.Symbol') && ... | |
21 | strcmp(ast.get(1).get(1).name, 'splice-unquote') | |
22 | ret = types.List(types.Symbol('concat'), ... | |
23 | ast.get(1).get(2), ... | |
24 | quasiquote(ast.slice(2))); | |
c4033aab | 25 | else |
6a572dff JM |
26 | ret = types.List(types.Symbol('cons'), ... |
27 | quasiquote(ast.get(1)), ... | |
28 | quasiquote(ast.slice(2))); | |
c4033aab JM |
29 | end |
30 | end | |
31 | ||
32 | function ret = is_macro_call(ast, env) | |
6a572dff JM |
33 | if types.list_Q(ast) && isa(ast.get(1), 'types.Symbol') && ... |
34 | ~islogical(env.find(ast.get(1))) | |
35 | f = env.get(ast.get(1)); | |
7f567f36 | 36 | ret = isa(f,'types.Function') && f.is_macro; |
c4033aab JM |
37 | else |
38 | ret = false; | |
39 | end | |
40 | end | |
41 | ||
42 | function ret = macroexpand(ast, env) | |
43 | while is_macro_call(ast, env) | |
6a572dff JM |
44 | mac = env.get(ast.get(1)); |
45 | args = ast.slice(2); | |
46 | ast = mac.fn(args.data{:}); | |
c4033aab JM |
47 | end |
48 | ret = ast; | |
49 | end | |
50 | ||
51 | function ret = eval_ast(ast, env) | |
52 | switch class(ast) | |
53 | case 'types.Symbol' | |
54 | ret = env.get(ast); | |
6a572dff JM |
55 | case 'types.List' |
56 | ret = types.List(); | |
c4033aab | 57 | for i=1:length(ast) |
6a572dff JM |
58 | ret.append(EVAL(ast.get(i), env)); |
59 | end | |
60 | case 'types.Vector' | |
61 | ret = types.Vector(); | |
62 | for i=1:length(ast) | |
63 | ret.append(EVAL(ast.get(i), env)); | |
64 | end | |
65 | case 'types.HashMap' | |
66 | ret = types.HashMap(); | |
67 | ks = ast.keys(); | |
68 | for i=1:length(ks) | |
69 | k = ks{i}; | |
70 | ret.set(EVAL(k, env), EVAL(ast.get(k), env)); | |
c4033aab JM |
71 | end |
72 | otherwise | |
73 | ret = ast; | |
74 | end | |
75 | end | |
76 | ||
77 | function ret = EVAL(ast, env) | |
78 | while true | |
6a572dff | 79 | if ~types.list_Q(ast) |
c4033aab JM |
80 | ret = eval_ast(ast, env); |
81 | return; | |
82 | end | |
83 | ||
84 | % apply | |
85 | ast = macroexpand(ast, env); | |
6a572dff | 86 | if ~types.list_Q(ast) |
c4033aab JM |
87 | ret = ast; |
88 | return; | |
89 | end | |
90 | ||
6a572dff JM |
91 | if isa(ast.get(1),'types.Symbol') |
92 | a1sym = ast.get(1).name; | |
c4033aab JM |
93 | else |
94 | a1sym = '_@$fn$@_'; | |
95 | end | |
96 | switch (a1sym) | |
97 | case 'def!' | |
6a572dff | 98 | ret = env.set(ast.get(2), EVAL(ast.get(3), env)); |
c4033aab JM |
99 | return; |
100 | case 'let*' | |
101 | let_env = Env(env); | |
6a572dff JM |
102 | for i=1:2:length(ast.get(2)) |
103 | let_env.set(ast.get(2).get(i), EVAL(ast.get(2).get(i+1), let_env)); | |
c4033aab JM |
104 | end |
105 | env = let_env; | |
6a572dff | 106 | ast = ast.get(3); % TCO |
c4033aab | 107 | case 'quote' |
6a572dff | 108 | ret = ast.get(2); |
c4033aab JM |
109 | return; |
110 | case 'quasiquote' | |
6a572dff | 111 | ast = quasiquote(ast.get(2)); % TCO |
c4033aab | 112 | case 'defmacro!' |
6a572dff | 113 | ret = env.set(ast.get(2), EVAL(ast.get(3), env)); |
c4033aab JM |
114 | ret.is_macro = true; |
115 | return; | |
116 | case 'macroexpand' | |
6a572dff | 117 | ret = macroexpand(ast.get(2), env); |
c4033aab JM |
118 | return; |
119 | case 'do' | |
6a572dff JM |
120 | el = eval_ast(ast.slice(2,length(ast)-1), env); |
121 | ast = ast.get(length(ast)); % TCO | |
c4033aab | 122 | case 'if' |
6a572dff | 123 | cond = EVAL(ast.get(2), env); |
c4033aab JM |
124 | if strcmp(class(cond), 'types.Nil') || ... |
125 | (islogical(cond) && cond == false) | |
126 | if length(ast) > 3 | |
6a572dff | 127 | ast = ast.get(4); % TCO |
c4033aab JM |
128 | else |
129 | ret = types.nil; | |
130 | return; | |
131 | end | |
132 | else | |
6a572dff | 133 | ast = ast.get(3); % TCO |
c4033aab JM |
134 | end |
135 | case 'fn*' | |
6a572dff JM |
136 | fn = @(varargin) EVAL(ast.get(3), Env(env, ast.get(2), ... |
137 | types.List(varargin{:}))); | |
138 | ret = types.Function(fn, ast.get(3), env, ast.get(2)); | |
c4033aab JM |
139 | return; |
140 | otherwise | |
141 | el = eval_ast(ast, env); | |
6a572dff JM |
142 | f = el.get(1); |
143 | args = el.slice(2); | |
b550d8b7 | 144 | if isa(f, 'types.Function') |
c4033aab JM |
145 | env = Env(f.env, f.params, args); |
146 | ast = f.ast; % TCO | |
147 | else | |
6a572dff | 148 | ret = f(args.data{:}); |
c4033aab JM |
149 | return |
150 | end | |
151 | end | |
152 | end | |
153 | end | |
154 | ||
155 | ||
156 | function ret = PRINT(ast) | |
157 | ret = printer.pr_str(ast, true); | |
158 | end | |
159 | ||
160 | % REPL | |
161 | function ret = rep(str, env) | |
162 | ret = PRINT(EVAL(READ(str), env)); | |
163 | end | |
164 | ||
165 | function main(args) | |
166 | repl_env = Env(false); | |
167 | ||
168 | % core.m: defined using matlab | |
169 | ns = core.ns(); ks = ns.keys(); | |
170 | for i=1:length(ks) | |
171 | k = ks{i}; | |
172 | repl_env.set(types.Symbol(k), ns(k)); | |
173 | end | |
174 | repl_env.set(types.Symbol('eval'), @(a) EVAL(a, repl_env)); | |
6a572dff JM |
175 | rest_args = args(2:end); |
176 | repl_env.set(types.Symbol('*ARGV*'), types.List(rest_args{:})); | |
c4033aab JM |
177 | |
178 | % core.mal: defined using the langauge itself | |
179 | rep('(def! not (fn* (a) (if a false true)))', repl_env); | |
180 | rep('(def! load-file (fn* (f) (eval (read-string (str "(do " (slurp f) ")")))))"', repl_env); | |
181 | rep('(defmacro! cond (fn* (& xs) (if (> (count xs) 0) (list ''if (first xs) (if (> (count xs) 1) (nth xs 1) (throw "odd number of forms to cond")) (cons ''cond (rest (rest xs)))))))', repl_env); | |
182 | rep('(defmacro! or (fn* (& xs) (if (empty? xs) nil (if (= 1 (count xs)) (first xs) `(let* (or_FIXME ~(first xs)) (if or_FIXME or_FIXME (or ~@(rest xs))))))))', repl_env); | |
183 | ||
184 | if ~isempty(args) | |
185 | rep(strcat('(load-file "', args{1}, '")'), repl_env); | |
186 | quit; | |
187 | end | |
188 | ||
189 | %cleanObj = onCleanup(@() disp('*** here1 ***')); | |
190 | while (true) | |
191 | line = input('user> ', 's'); | |
192 | if strcmp(strtrim(line),''), continue, end | |
193 | try | |
194 | fprintf('%s\n', rep(line, repl_env)); | |
195 | catch err | |
196 | fprintf('Error: %s\n', err.message); | |
197 | fprintf('%s\n', getReport(err, 'extended')); | |
198 | end | |
199 | end | |
200 | end |