72 lines
2.4 KiB
TypeScript
72 lines
2.4 KiB
TypeScript
|
export * from './utils.js';
|
||
|
|
type MatchFn = (ch: number) => boolean;
|
||
|
|
/**
|
||
|
|
* A streaming, character code-based string reader
|
||
|
|
*/
|
||
|
|
export default class Scanner {
|
||
|
|
/** Current string */
|
||
|
|
string: string;
|
||
|
|
/** Current scanner position */
|
||
|
|
pos: number;
|
||
|
|
/** Lower range limit where string reader is available */
|
||
|
|
start: number;
|
||
|
|
/** Upper range limit where string reader is available */
|
||
|
|
end: number;
|
||
|
|
constructor(str: string, start?: number, end?: number);
|
||
|
|
/**
|
||
|
|
* Returns true only if the stream is at the end of the file.
|
||
|
|
*/
|
||
|
|
eof(): boolean;
|
||
|
|
/**
|
||
|
|
* Creates a new stream instance which is limited to given `start` and `end`
|
||
|
|
* range. E.g. its `eof()` method will look at `end` property, not actual
|
||
|
|
* stream end
|
||
|
|
*/
|
||
|
|
limit(start?: number, end?: number): Scanner;
|
||
|
|
/**
|
||
|
|
* Returns the next character code in the stream without advancing it.
|
||
|
|
* Will return NaN at the end of the file.
|
||
|
|
*/
|
||
|
|
peek(): number;
|
||
|
|
/**
|
||
|
|
* Returns the next character in the stream and advances it.
|
||
|
|
* Also returns <code>undefined</code> when no more characters are available.
|
||
|
|
*/
|
||
|
|
next(): number | undefined;
|
||
|
|
/**
|
||
|
|
* `match` can be a character code or a function that takes a character code
|
||
|
|
* and returns a boolean. If the next character in the stream 'matches'
|
||
|
|
* the given argument, it is consumed and returned.
|
||
|
|
* Otherwise, `false` is returned.
|
||
|
|
*/
|
||
|
|
eat(match: number | MatchFn): boolean;
|
||
|
|
/**
|
||
|
|
* Repeatedly calls <code>eat</code> with the given argument, until it
|
||
|
|
* fails. Returns <code>true</code> if any characters were eaten.
|
||
|
|
*/
|
||
|
|
eatWhile(match: number | MatchFn): boolean;
|
||
|
|
/**
|
||
|
|
* Backs up the stream n characters. Backing it up further than the
|
||
|
|
* start of the current token will cause things to break, so be careful.
|
||
|
|
*/
|
||
|
|
backUp(n: number): void;
|
||
|
|
/**
|
||
|
|
* Get the string between the start of the current token and the
|
||
|
|
* current stream position.
|
||
|
|
*/
|
||
|
|
current(): string;
|
||
|
|
/**
|
||
|
|
* Returns substring for given range
|
||
|
|
*/
|
||
|
|
substring(start: number, end?: number): string;
|
||
|
|
/**
|
||
|
|
* Creates error object with current stream state
|
||
|
|
*/
|
||
|
|
error(message: string, pos?: number): ScannerError;
|
||
|
|
}
|
||
|
|
export declare class ScannerError extends Error {
|
||
|
|
pos: number;
|
||
|
|
string: string;
|
||
|
|
constructor(message: string, pos: number, str: string);
|
||
|
|
}
|