|
1
|
|
|
<?php |
|
2
|
|
|
|
|
3
|
|
|
|
|
4
|
|
|
namespace App; |
|
5
|
|
|
|
|
6
|
|
|
|
|
7
|
|
|
use App\Exception\ParseError; |
|
8
|
|
|
use App\Node\BinaryOperator; |
|
9
|
|
|
use App\Node\FunctionCall; |
|
10
|
|
|
use App\Node\Integer; |
|
11
|
|
|
use App\Node\Real; |
|
12
|
|
|
use App\Node\UnaryOperator; |
|
13
|
|
|
use App\Node\Visitable; |
|
14
|
|
|
|
|
15
|
|
|
class Parser |
|
16
|
|
|
{ |
|
17
|
|
|
/** |
|
18
|
|
|
* @var Lexer |
|
19
|
|
|
*/ |
|
20
|
|
|
private $lexer; |
|
21
|
|
|
|
|
22
|
|
|
/** |
|
23
|
|
|
* @var Token |
|
24
|
|
|
*/ |
|
25
|
|
|
private $currentToken; |
|
26
|
|
|
|
|
27
|
|
|
/** |
|
28
|
|
|
* Parser constructor. |
|
29
|
|
|
* @param Lexer $lexer |
|
30
|
|
|
* @throws Exception\LexerException |
|
31
|
|
|
* @throws Exception\UnknownIdentifier |
|
32
|
|
|
*/ |
|
33
|
|
|
public function __construct( |
|
34
|
|
|
Lexer $lexer |
|
35
|
|
|
) |
|
36
|
|
|
{ |
|
37
|
|
|
$this->lexer = $lexer; |
|
38
|
|
|
$this->currentToken = $this->lexer->getNextToken(); |
|
39
|
|
|
} |
|
40
|
|
|
|
|
41
|
|
|
/** |
|
42
|
|
|
* @param string $tokenType |
|
43
|
|
|
* @throws Exception\LexerException |
|
44
|
|
|
* @throws ParseError |
|
45
|
|
|
* @throws Exception\UnknownIdentifier |
|
46
|
|
|
*/ |
|
47
|
|
|
private function eat(string $tokenType): void |
|
48
|
|
|
{ |
|
49
|
|
|
if ($this->currentToken->type === $tokenType) { |
|
50
|
|
|
$this->currentToken = $this->lexer->getNextToken(); |
|
51
|
|
|
} else { |
|
52
|
|
|
throw new ParseError('Wrong token type'); |
|
53
|
|
|
} |
|
54
|
|
|
} |
|
55
|
|
|
|
|
56
|
|
|
/** |
|
57
|
|
|
* @return FunctionCall |
|
58
|
|
|
* @throws Exception\LexerException |
|
59
|
|
|
* @throws Exception\UnknownIdentifier |
|
60
|
|
|
* @throws ParseError |
|
61
|
|
|
*/ |
|
62
|
|
|
private function parseFunction(): FunctionCall |
|
63
|
|
|
{ |
|
64
|
|
|
$token = $this->currentToken; |
|
65
|
|
|
$this->eat(Token::FUNCTION_CALL); |
|
66
|
|
|
$this->eat(Token::LPAREN); |
|
67
|
|
|
$args = []; |
|
68
|
|
|
|
|
69
|
|
|
while (true) { |
|
70
|
|
|
$args[] = $this->expr(); |
|
71
|
|
|
if ($this->currentToken->type === Token::COMMA) { |
|
72
|
|
|
$this->eat(Token::COMMA); |
|
73
|
|
|
} else { |
|
74
|
|
|
break; |
|
75
|
|
|
} |
|
76
|
|
|
} |
|
77
|
|
|
|
|
78
|
|
|
$this->eat(Token::RPAREN); |
|
79
|
|
|
|
|
80
|
|
|
return new FunctionCall($token, $args); |
|
81
|
|
|
} |
|
82
|
|
|
|
|
83
|
|
|
/** |
|
84
|
|
|
* @return Visitable |
|
85
|
|
|
* @throws Exception\LexerException |
|
86
|
|
|
* @throws ParseError |
|
87
|
|
|
* @throws Exception\UnknownIdentifier |
|
88
|
|
|
*/ |
|
89
|
|
|
private function factor(): Visitable |
|
90
|
|
|
{ |
|
91
|
|
|
$token = $this->currentToken; |
|
92
|
|
|
|
|
93
|
|
|
if ($token->type === Token::PLUS) { |
|
94
|
|
|
$this->eat(Token::PLUS); |
|
95
|
|
|
return new UnaryOperator($token, $this->factor()); |
|
96
|
|
|
} |
|
97
|
|
|
if ($token->type === Token::MINUS) { |
|
98
|
|
|
$this->eat(Token::MINUS); |
|
99
|
|
|
return new UnaryOperator($token, $this->factor()); |
|
100
|
|
|
} |
|
101
|
|
|
|
|
102
|
|
|
if ($token->type === Token::INT) { |
|
103
|
|
|
$this->eat(Token::INT); |
|
104
|
|
|
return new Integer((int)$token->value); |
|
105
|
|
|
} |
|
106
|
|
|
|
|
107
|
|
|
if ($token->type === Token::REAL) { |
|
108
|
|
|
$this->eat(Token::REAL); |
|
109
|
|
|
return new Real((float)$token->value); |
|
110
|
|
|
} |
|
111
|
|
|
|
|
112
|
|
|
if ($token->type === Token::FUNCTION_CALL) { |
|
113
|
|
|
return $this->parseFunction(); |
|
114
|
|
|
} |
|
115
|
|
|
|
|
116
|
|
|
if ($token->type === Token::LPAREN) { |
|
117
|
|
|
$this->eat(Token::LPAREN); |
|
118
|
|
|
$node = $this->expr(); |
|
119
|
|
|
$this->eat(Token::RPAREN); |
|
120
|
|
|
return $node; |
|
121
|
|
|
} |
|
122
|
|
|
|
|
123
|
|
|
throw new ParseError('Unknown factor type'); |
|
124
|
|
|
} |
|
125
|
|
|
|
|
126
|
|
|
/** |
|
127
|
|
|
* @return Visitable |
|
128
|
|
|
* @throws Exception\LexerException |
|
129
|
|
|
* @throws ParseError |
|
130
|
|
|
* @throws Exception\UnknownIdentifier |
|
131
|
|
|
*/ |
|
132
|
|
|
private function term(): Visitable |
|
133
|
|
|
{ |
|
134
|
|
|
$node = $this->factor(); |
|
135
|
|
|
|
|
136
|
|
|
while (in_array($this->currentToken->type, [Token::MUL, Token::REALDIV, Token::POWER], true)) { |
|
137
|
|
|
/** @var Token $operator */ |
|
138
|
|
|
$operator = $this->currentToken; |
|
139
|
|
|
/** @psalm-suppress PossiblyNullArgument */ |
|
140
|
|
|
$this->eat($this->currentToken->type); |
|
141
|
|
|
$node = new BinaryOperator($node, $operator, $this->factor()); |
|
142
|
|
|
} |
|
143
|
|
|
|
|
144
|
|
|
return $node; |
|
145
|
|
|
} |
|
146
|
|
|
|
|
147
|
|
|
/** |
|
148
|
|
|
* @return Visitable |
|
149
|
|
|
* @throws Exception\LexerException |
|
150
|
|
|
* @throws ParseError |
|
151
|
|
|
* @throws Exception\UnknownIdentifier |
|
152
|
|
|
*/ |
|
153
|
|
|
private function expr(): Visitable |
|
154
|
|
|
{ |
|
155
|
|
|
$node = $this->term(); |
|
156
|
|
|
|
|
157
|
|
|
while (in_array($this->currentToken->type, [Token::PLUS, Token::MINUS], true)) { |
|
158
|
|
|
/** @var Token $operator */ |
|
159
|
|
|
$operator = $this->currentToken; |
|
160
|
|
|
/** @psalm-suppress PossiblyNullArgument */ |
|
161
|
|
|
$this->eat($this->currentToken->type); |
|
162
|
|
|
$node = new BinaryOperator($node, $operator, $this->term()); |
|
163
|
|
|
} |
|
164
|
|
|
|
|
165
|
|
|
return $node; |
|
166
|
|
|
} |
|
167
|
|
|
|
|
168
|
|
|
/** |
|
169
|
|
|
* @return Visitable |
|
170
|
|
|
* @throws Exception\LexerException |
|
171
|
|
|
* @throws ParseError |
|
172
|
|
|
* @throws Exception\UnknownIdentifier |
|
173
|
|
|
*/ |
|
174
|
|
|
public function parse(): Visitable |
|
175
|
|
|
{ |
|
176
|
|
|
return $this->expr(); |
|
177
|
|
|
} |
|
178
|
|
|
} |
drumser /
arithmetic-parser
