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import { SyntaxError } from './SyntaxError.js';
const TAB = 9;
const N = 10;
const F = 12;
const R = 13;
const SPACE = 32;
export class Tokenizer {
constructor(str) {
this.str = str;
this.pos = 0;
}
charCodeAt(pos) {
return pos < this.str.length ? this.str.charCodeAt(pos) : 0;
}
charCode() {
return this.charCodeAt(this.pos);
}
nextCharCode() {
return this.charCodeAt(this.pos + 1);
}
nextNonWsCode(pos) {
return this.charCodeAt(this.findWsEnd(pos));
}
findWsEnd(pos) {
for (; pos < this.str.length; pos++) {
const code = this.str.charCodeAt(pos);
if (code !== R && code !== N && code !== F && code !== SPACE && code !== TAB) {
break;
}
}
return pos;
}
substringToPos(end) {
return this.str.substring(this.pos, this.pos = end);
}
eat(code) {
if (this.charCode() !== code) {
this.error('Expect `' + String.fromCharCode(code) + '`');
}
this.pos++;
}
peek() {
return this.pos < this.str.length ? this.str.charAt(this.pos++) : '';
}
error(message) {
throw new SyntaxError(message, this.str, this.pos);
}
};