collectype

collectype v0.11.0


collectype / factory/strings/stringPattern / stringPatternFactory

Function: stringPatternFactory()

stringPatternFactory<T, C>(ctx, oper): <K>(field, target) => C

Defined in: factory/strings/stringPattern.ts:40

Creates a predicate filter for string pattern using PredicType.string.pattern.

Type Parameters

T

T

The item type in the collection.

C

C extends Wherable<T, C>

The Wherable context type (must extend Wherable<T, C>).

Parameters

ctx

C

The context (usually a collection) supporting the where method.

oper

StringPatternOper

The string pattern operation to perform (see PredicType.string.pattern).

Returns

Returns a function that takes a field (of type string on T) and a pattern, and applies the string pattern predicate to filter the context.

<K>(field, target): C

Type Parameters

K

K extends string | number | symbol

Parameters

field

K

target

RegExp

Returns

C

Example

// Example: Composing a string pattern filter as a property, homogeneous model
import { BaseFunctions } from 'collectype';
import { stringPatternFactory } from 'collectype';

type Person = { name: string; city: string };

class PersonFunctions extends BaseFunctions<Person> {
  stringMatchesPattern = stringPatternFactory<Person, this>(this, 'matches');
}

// Usage:
const people: Person[] = [
  { name: 'Alice', city: 'Paris' },
  { name: 'Bob', city: 'Lyon' },
  { name: 'Eve', city: 'Paris' }
];
const fn = new PersonFunctions(people);
const filtered = fn.stringMatchesPattern('city', /^Pa/);
// filtered contains the items where 'city' starts with 'Pa'

Remarks