87 lines
1.4 KiB
C
87 lines
1.4 KiB
C
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#include "lexer.h"
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#include <string.h>
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#include <stdlib.h>
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#include <stdio,h>
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Lexer initLexer(char *source) {
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Lexer newLexer = {
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.source = source,
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.position = -1,
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.readPosition = 0,
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.lineNumber = 1,
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.currentChar = '\0'
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};
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return newLexer;
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}
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void readChar(Lexer *lexer) {
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if (lexer->readPosition >= strlen(lexer->source))
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lexer->currentChar = '\0';
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else
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lexer->currentChar = lexer->source[lexer->readPosition];
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lexer->position = lexer->readPosition;
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lexer->readPosition++;
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}
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void skipWhitespace(Lexer *lexer) {
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switch (lexer->currentChar)
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{
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case ' ':
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case '\t':
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case '\n':
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case '\r':
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if (lexer->currentChar == '\n')
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lexer->lineNumber++;
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readChar(lexer);
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break;
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default:
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break;
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}
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}
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Token nextToken(Lexer *lexer) {
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//Token tok;
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skipWhitespace(lexer);
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switch (lexer->currentChar)
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{
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case '+':
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return NEW_TOKEN(lexer, PLUS, "+");
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break;
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case '-':
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return NEW_TOKEN(lexer, MINUS, "-");
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break;
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case '*':
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return NEW_TOKEN(lexer, ASTERISK, "*");
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break;
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case '/':
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return NEW_TOKEN(lexer, SLASH, "/");
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break;
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case '%':
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return NEW_TOKEN(lexer, MODULUS, "%");
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break;
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case '^':
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return NEW_TOKEN(lexer, POW, "^");
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break;
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case '(':
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return NEW_TOKEN(lexer, LPAREN, "(");
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break;
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case ')':
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return NEW_TOKEN(lexer, RPAREN, ")");
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break;
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case '\0':
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return NEW_TOKEN(lexer, EOF, "");
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break;
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default:
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if (isdigit())
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break;
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}
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//return tok;
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}
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