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formatInterpolate

Generate string from a token array by interpolating values.

Usage

import formatInterpolate from 'https://cdn.jsdelivr.net/gh/stdlib-js/string-base-format-interpolate@deno/mod.js';

formatInterpolate( tokens, ...args )

Generates string from a token array by interpolating values.

import formatTokenize from 'https://cdn.jsdelivr.net/gh/stdlib-js/string-base-format-tokenize@deno/mod.js';

var str = 'Hello, %s! My name is %s.';
var tokens = formatTokenize( str );
var out = formatInterpolate( tokens, 'World', 'Bob' );
// returns 'Hello, World! My name is Bob.'

The array of tokens should contain string parts and format identifier objects.

var tokens = [ 'beep ', { 'specifier': 's' } ];
var out = formatInterpolate( tokens, 'boop' );
// returns 'beep boop'

Format identifier objects can have the following properties:

property	description
specifier	format specifier (one of 's', 'c', 'd', 'i', 'u', 'b', 'o', 'x', 'X', 'e', 'E', 'f', 'F', 'g', 'G')
flags	format flags (string with any of '0', ' ', '+', '-', '#')
width	minimum field width (integer or `'*'`)
precision	precision (integer or `'*'`)
mapping	positional mapping from format specifier to argument index

Examples

import formatTokenize from 'https://cdn.jsdelivr.net/gh/stdlib-js/string-base-format-tokenize@deno/mod.js';
import PI from 'https://cdn.jsdelivr.net/gh/stdlib-js/constants-float64-pi@deno/mod.js';
import formatInterpolate from 'https://cdn.jsdelivr.net/gh/stdlib-js/string-base-format-interpolate@deno/mod.js';

var tokens = formatTokenize( 'Hello %s!' );
var out = formatInterpolate( tokens, 'World' );
// returns 'Hello World!'

tokens = formatTokenize( 'Pi: ~%.2f' );
out = formatInterpolate( tokens, PI );
// returns 'Pi: ~3.14'

tokens = formatTokenize( 'Index: %d, Value: %s' );
out = formatInterpolate( tokens, 0, 'foo' );
// returns 'Index: 0, Value: foo'

See Also

@stdlib/string-base/format-tokenize: tokenize a string into an array of string parts and format identifier objects.

Notice

This package is part of stdlib, a standard library with an emphasis on numerical and scientific computing. The library provides a collection of robust, high performance libraries for mathematics, statistics, streams, utilities, and more.

For more information on the project, filing bug reports and feature requests, and guidance on how to develop stdlib, see the main project repository.

Community

License

See LICENSE.

Copyright

Copyright © 2016-2025. The Stdlib Authors.

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