Returning letter
I am writing the coding which is display the contain of the file is number,letter,...etc but I stuck on the keyword part
Let say i have if is written in the file and that if is see it should be display keyword not indent
can someone help me out plz
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
|
/
#include "LexicalAnalysis.h"
LexicalAnalysis::LexicalAnalysis(string in) : input(in), charClass(ERROR), nextChar(' '), lexeme("")
{
getChar();
}
LexicalAnalysis::~LexicalAnalysis()
{
}
void LexicalAnalysis::setNewInput(string in)
{
input=in;
getChar();
}
void LexicalAnalysis::getChar()
{
if (input.size()>0)
{
nextChar = input[0];
input.erase(0,1);
}
else nextChar = '$';
charClass = ERROR;
if ( (nextChar > 64 && nextChar <91) || (nextChar > 96 && nextChar <123) )
charClass = LETTER;
if ( nextChar > 47 && nextChar <58 )
charClass = DIGIT;
if (nextChar == ' ') charClass = SPACE;
if (nextChar == '$') charClass = STOP;
if (nextChar == 'i') charClass = PLUS_CODE;
}
void LexicalAnalysis::addChar()
{
lexeme+=nextChar;
}
int LexicalAnalysis::lex()
{
lexeme="";
while (charClass == SPACE) getChar();
if (charClass == ERROR) {addChar(); getChar(); return ERROR;}
if (charClass == STOP) { return STOP;}
switch (charClass) {
case LETTER:
addChar();
getChar();
while (charClass == LETTER || charClass == DIGIT)
{
addChar();
getChar();
}
return IDENT;
break;
case DIGIT:
addChar();
getChar();
while (charClass == DIGIT) {
addChar();
getChar();
}
return INT_LIT;
break;
case PLUS_CODE:
addChar();
getChar();
return PLUS_CODE;
break;
}
return 0;
}
| |
Topic archived. No new replies allowed.