collectype

collectype v0.11.0


collectype / factory/strings/stringSubstring / stringSubstringFactory

Function: stringSubstringFactory()

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

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

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

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

StringSubstringOper

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

Returns

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

<K>(field, target): C

Type Parameters

K

K extends string | number | symbol

Parameters

field

K

target

string

Returns

C

Example

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

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

class PersonFunctions extends BaseFunctions<Person> {
  stringContains = stringSubstringFactory<Person, this>(this, 'contains');
}

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

Remarks