blob: c09f499c30f9fda5894a04b52e5ec63700b1f6ee (
plain)
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
|
# Grammar for Chapter 7
English | [日本語](07-grammar.ja.md)
```antlrv4
grammar SimpleLanguage;
program
: statement+ EOF
;
statement
: returnStatement
| declStatement
| blockStatment
| expressionStatement
| ifStatement
| whileStatement
;
whileStatement
: 'while' '(' expression ')' statement
;
ifStatement
: 'if' '(' expression ')' statement ('else' statement)?
;
expressionStatement
: IDENTIFIER '=' expression ';'
;
blockStatement
: '{' statement+ '}'
;
declStatement
: 'int' IDENTIFIER '=' expression ';'
;
returnStatement
: 'return' expression ';'
;
expression
: comparisonExpression
;
comparisonExpression
: additiveExpression (('==' | '!='| '>'| '<'| '>='| '<=') additiveExpression)*
;
additiveExpression
: multiplicativeExpression (('+' | '-') multiplicativeExpression)*
;
multiplicativeExpression
: unaryExpression (('*' | '/') unaryExpression)*
;
unaryExpression
: ('-') unaryExpression
| primaryExpression
;
primaryExpression
: IDENTIFIER
| INTEGER_LITERAL
| 'true'
| 'false'
| '(' expression ')'
;
INTEGER_LITERAL
: [1-9][0-9]*
| [0]
;
IDENTIFIER
: NON_DIGIT (NON_DIGIT | DIGIT)*
;
NON_DIGIT: [a-zA-Z_];
DEC_DIGIT: [0-9];
```
|
