rustleaf 0.1.0

A simple programming language interpreter written in Rust
Documentation
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
# Program
Status: 🟢
Assertions: 3

```rustleaf
var result1 = if true { 42 } else { 0 };
var result2 = if false { 100 } else { 200 };
var x = 5;
var result3 = if x > 3 { "big" } else { "small" };
assert(result1 == 42);
assert(result2 == 200);
assert(result3 == "big");
```

# Output
```
parse_program: starting
parse_program: parsing statement at position 0 (Var)
parse_statement: starting at position 0 (Var)
consume_token: position 0 consumed Var
consume_token: position 1 consumed Ident
consume_token: position 2 consumed Equal
parse_expression: starting at position 3 (If)
consume_token: position 3 consumed If
parse_primary: success - parsing if expression
parse_expression: starting at position 4 (True)
consume_token: position 4 consumed True
parse_primary: success - parsed boolean literal (true)
parse_expression: success - parsed precedence expression
consume_token: position 5 consumed LeftBrace
parse_statement: starting at position 6 (Int(42))
parse_statement: falling back to expression statement
parse_expression: starting at position 6 (Int(42))
consume_token: position 6 consumed Int
parse_primary: success - parsed numeric/string literal
parse_expression: success - parsed precedence expression
parse_statement: failed - Expected Semicolon, found RightBrace at position 7
parse_expression: starting at position 6 (Int(42))
consume_token: position 6 consumed Int
parse_primary: success - parsed numeric/string literal
parse_expression: success - parsed precedence expression
consume_token: position 7 consumed RightBrace
consume_token: position 8 consumed Else
consume_token: position 9 consumed LeftBrace
parse_statement: starting at position 10 (Int(0))
parse_statement: falling back to expression statement
parse_expression: starting at position 10 (Int(0))
consume_token: position 10 consumed Int
parse_primary: success - parsed numeric/string literal
parse_expression: success - parsed precedence expression
parse_statement: failed - Expected Semicolon, found RightBrace at position 11
parse_expression: starting at position 10 (Int(0))
consume_token: position 10 consumed Int
parse_primary: success - parsed numeric/string literal
parse_expression: success - parsed precedence expression
consume_token: position 11 consumed RightBrace
parse_expression: success - parsed precedence expression
consume_token: position 12 consumed Semicolon
parse_statement: success - parsed var declaration
parse_program: parsing statement at position 13 (Var)
parse_statement: starting at position 13 (Var)
consume_token: position 13 consumed Var
consume_token: position 14 consumed Ident
consume_token: position 15 consumed Equal
parse_expression: starting at position 16 (If)
consume_token: position 16 consumed If
parse_primary: success - parsing if expression
parse_expression: starting at position 17 (False)
consume_token: position 17 consumed False
parse_primary: success - parsed boolean literal (false)
parse_expression: success - parsed precedence expression
consume_token: position 18 consumed LeftBrace
parse_statement: starting at position 19 (Int(100))
parse_statement: falling back to expression statement
parse_expression: starting at position 19 (Int(100))
consume_token: position 19 consumed Int
parse_primary: success - parsed numeric/string literal
parse_expression: success - parsed precedence expression
parse_statement: failed - Expected Semicolon, found RightBrace at position 20
parse_expression: starting at position 19 (Int(100))
consume_token: position 19 consumed Int
parse_primary: success - parsed numeric/string literal
parse_expression: success - parsed precedence expression
consume_token: position 20 consumed RightBrace
consume_token: position 21 consumed Else
consume_token: position 22 consumed LeftBrace
parse_statement: starting at position 23 (Int(200))
parse_statement: falling back to expression statement
parse_expression: starting at position 23 (Int(200))
consume_token: position 23 consumed Int
parse_primary: success - parsed numeric/string literal
parse_expression: success - parsed precedence expression
parse_statement: failed - Expected Semicolon, found RightBrace at position 24
parse_expression: starting at position 23 (Int(200))
consume_token: position 23 consumed Int
parse_primary: success - parsed numeric/string literal
parse_expression: success - parsed precedence expression
consume_token: position 24 consumed RightBrace
parse_expression: success - parsed precedence expression
consume_token: position 25 consumed Semicolon
parse_statement: success - parsed var declaration
parse_program: parsing statement at position 26 (Var)
parse_statement: starting at position 26 (Var)
consume_token: position 26 consumed Var
consume_token: position 27 consumed Ident
consume_token: position 28 consumed Equal
parse_expression: starting at position 29 (Int(5))
consume_token: position 29 consumed Int
parse_primary: success - parsed numeric/string literal
parse_expression: success - parsed precedence expression
consume_token: position 30 consumed Semicolon
parse_statement: success - parsed var declaration
parse_program: parsing statement at position 31 (Var)
parse_statement: starting at position 31 (Var)
consume_token: position 31 consumed Var
consume_token: position 32 consumed Ident
consume_token: position 33 consumed Equal
parse_expression: starting at position 34 (If)
consume_token: position 34 consumed If
parse_primary: success - parsing if expression
parse_expression: starting at position 35 (Ident(x))
consume_token: position 35 consumed Ident
parse_primary: success - parsed identifier (x)
consume_token: position 36 consumed Greater
consume_token: position 37 consumed Int
parse_primary: success - parsed numeric/string literal
parse_expression: success - parsed precedence expression
consume_token: position 38 consumed LeftBrace
parse_statement: starting at position 39 (String(big))
parse_statement: falling back to expression statement
parse_expression: starting at position 39 (String(big))
consume_token: position 39 consumed String
parse_primary: success - parsed numeric/string literal
parse_expression: success - parsed precedence expression
parse_statement: failed - Expected Semicolon, found RightBrace at position 40
parse_expression: starting at position 39 (String(big))
consume_token: position 39 consumed String
parse_primary: success - parsed numeric/string literal
parse_expression: success - parsed precedence expression
consume_token: position 40 consumed RightBrace
consume_token: position 41 consumed Else
consume_token: position 42 consumed LeftBrace
parse_statement: starting at position 43 (String(small))
parse_statement: falling back to expression statement
parse_expression: starting at position 43 (String(small))
consume_token: position 43 consumed String
parse_primary: success - parsed numeric/string literal
parse_expression: success - parsed precedence expression
parse_statement: failed - Expected Semicolon, found RightBrace at position 44
parse_expression: starting at position 43 (String(small))
consume_token: position 43 consumed String
parse_primary: success - parsed numeric/string literal
parse_expression: success - parsed precedence expression
consume_token: position 44 consumed RightBrace
parse_expression: success - parsed precedence expression
consume_token: position 45 consumed Semicolon
parse_statement: success - parsed var declaration
parse_program: parsing statement at position 46 (Ident(assert))
parse_statement: starting at position 46 (Ident(assert))
consume_token: position 46 consumed Ident
parse_statement: falling back to expression statement
parse_expression: starting at position 46 (Ident(assert))
consume_token: position 46 consumed Ident
parse_primary: success - parsed identifier (assert)
consume_token: position 47 consumed LeftParen
parse_expression: starting at position 48 (Ident(result1))
consume_token: position 48 consumed Ident
parse_primary: success - parsed identifier (result1)
consume_token: position 49 consumed EqualEqual
consume_token: position 50 consumed Int
parse_primary: success - parsed numeric/string literal
parse_expression: success - parsed precedence expression
consume_token: position 51 consumed RightParen
parse_expression: success - parsed precedence expression
consume_token: position 52 consumed Semicolon
parse_program: parsing statement at position 53 (Ident(assert))
parse_statement: starting at position 53 (Ident(assert))
consume_token: position 53 consumed Ident
parse_statement: falling back to expression statement
parse_expression: starting at position 53 (Ident(assert))
consume_token: position 53 consumed Ident
parse_primary: success - parsed identifier (assert)
consume_token: position 54 consumed LeftParen
parse_expression: starting at position 55 (Ident(result2))
consume_token: position 55 consumed Ident
parse_primary: success - parsed identifier (result2)
consume_token: position 56 consumed EqualEqual
consume_token: position 57 consumed Int
parse_primary: success - parsed numeric/string literal
parse_expression: success - parsed precedence expression
consume_token: position 58 consumed RightParen
parse_expression: success - parsed precedence expression
consume_token: position 59 consumed Semicolon
parse_program: parsing statement at position 60 (Ident(assert))
parse_statement: starting at position 60 (Ident(assert))
consume_token: position 60 consumed Ident
parse_statement: falling back to expression statement
parse_expression: starting at position 60 (Ident(assert))
consume_token: position 60 consumed Ident
parse_primary: success - parsed identifier (assert)
consume_token: position 61 consumed LeftParen
parse_expression: starting at position 62 (Ident(result3))
consume_token: position 62 consumed Ident
parse_primary: success - parsed identifier (result3)
consume_token: position 63 consumed EqualEqual
consume_token: position 64 consumed String
parse_primary: success - parsed numeric/string literal
parse_expression: success - parsed precedence expression
consume_token: position 65 consumed RightParen
parse_expression: success - parsed precedence expression
consume_token: position 66 consumed Semicolon
parse_program: parsed 7 statements
```

# Result
```rust
Ok(
    Unit,
)
```

# Lex
```rust
Ok(
    [
        0: Token(Var),
        1: Token(Ident, "result1"),
        2: Token(Equal),
        3: Token(If),
        4: Token(True),
        5: Token(LeftBrace),
        6: Token(Int, "42"),
        7: Token(RightBrace),
        8: Token(Else),
        9: Token(LeftBrace),
        10: Token(Int, "0"),
        11: Token(RightBrace),
        12: Token(Semicolon),
        13: Token(Var),
        14: Token(Ident, "result2"),
        15: Token(Equal),
        16: Token(If),
        17: Token(False),
        18: Token(LeftBrace),
        19: Token(Int, "100"),
        20: Token(RightBrace),
        21: Token(Else),
        22: Token(LeftBrace),
        23: Token(Int, "200"),
        24: Token(RightBrace),
        25: Token(Semicolon),
        26: Token(Var),
        27: Token(Ident, "x"),
        28: Token(Equal),
        29: Token(Int, "5"),
        30: Token(Semicolon),
        31: Token(Var),
        32: Token(Ident, "result3"),
        33: Token(Equal),
        34: Token(If),
        35: Token(Ident, "x"),
        36: Token(Greater),
        37: Token(Int, "3"),
        38: Token(LeftBrace),
        39: Token(String, "big"),
        40: Token(RightBrace),
        41: Token(Else),
        42: Token(LeftBrace),
        43: Token(String, "small"),
        44: Token(RightBrace),
        45: Token(Semicolon),
        46: Token(Ident, "assert"),
        47: Token(LeftParen),
        48: Token(Ident, "result1"),
        49: Token(EqualEqual),
        50: Token(Int, "42"),
        51: Token(RightParen),
        52: Token(Semicolon),
        53: Token(Ident, "assert"),
        54: Token(LeftParen),
        55: Token(Ident, "result2"),
        56: Token(EqualEqual),
        57: Token(Int, "200"),
        58: Token(RightParen),
        59: Token(Semicolon),
        60: Token(Ident, "assert"),
        61: Token(LeftParen),
        62: Token(Ident, "result3"),
        63: Token(EqualEqual),
        64: Token(String, "big"),
        65: Token(RightParen),
        66: Token(Semicolon),
        67: Token(Eof)
    ],
)
```

# Parse
```rust
Ok(
    Program(
        [
            VarDecl {
                pattern: Variable(
                    "result1",
                ),
                value: Some(
                    If {
                        condition: Literal(
                            Bool(
                                true,
                            ),
                        ),
                        then_expr: Block {
                            statements: [],
                            final_expr: Some(
                                Literal(
                                    Int(
                                        42,
                                    ),
                                ),
                            ),
                        },
                        else_expr: Some(
                            Block {
                                statements: [],
                                final_expr: Some(
                                    Literal(
                                        Int(
                                            0,
                                        ),
                                    ),
                                ),
                            },
                        ),
                    },
                ),
            },
            VarDecl {
                pattern: Variable(
                    "result2",
                ),
                value: Some(
                    If {
                        condition: Literal(
                            Bool(
                                false,
                            ),
                        ),
                        then_expr: Block {
                            statements: [],
                            final_expr: Some(
                                Literal(
                                    Int(
                                        100,
                                    ),
                                ),
                            ),
                        },
                        else_expr: Some(
                            Block {
                                statements: [],
                                final_expr: Some(
                                    Literal(
                                        Int(
                                            200,
                                        ),
                                    ),
                                ),
                            },
                        ),
                    },
                ),
            },
            VarDecl {
                pattern: Variable(
                    "x",
                ),
                value: Some(
                    Literal(
                        Int(
                            5,
                        ),
                    ),
                ),
            },
            VarDecl {
                pattern: Variable(
                    "result3",
                ),
                value: Some(
                    If {
                        condition: Gt(
                            Identifier(
                                "x",
                            ),
                            Literal(
                                Int(
                                    3,
                                ),
                            ),
                        ),
                        then_expr: Block {
                            statements: [],
                            final_expr: Some(
                                Literal(
                                    String(
                                        "big",
                                    ),
                                ),
                            ),
                        },
                        else_expr: Some(
                            Block {
                                statements: [],
                                final_expr: Some(
                                    Literal(
                                        String(
                                            "small",
                                        ),
                                    ),
                                ),
                            },
                        ),
                    },
                ),
            },
            Expression(
                FunctionCall(
                    Identifier(
                        "assert",
                    ),
                    [
                        Eq(
                            Identifier(
                                "result1",
                            ),
                            Literal(
                                Int(
                                    42,
                                ),
                            ),
                        ),
                    ],
                ),
            ),
            Expression(
                FunctionCall(
                    Identifier(
                        "assert",
                    ),
                    [
                        Eq(
                            Identifier(
                                "result2",
                            ),
                            Literal(
                                Int(
                                    200,
                                ),
                            ),
                        ),
                    ],
                ),
            ),
            Expression(
                FunctionCall(
                    Identifier(
                        "assert",
                    ),
                    [
                        Eq(
                            Identifier(
                                "result3",
                            ),
                            Literal(
                                String(
                                    "big",
                                ),
                            ),
                        ),
                    ],
                ),
            ),
        ],
    ),
)
```

# Eval
```rust
Ok(
    RustValue(<unknown>),
)
```