README
startsWith
Test if a string starts with the characters of another string.
Installation
npm install @stdlib/string-starts-with
Usage
var startsWith = require( '@stdlib/string-starts-with' );
startsWith( str, search[, position] )
Tests if a string
starts with the characters of another string
.
var str = 'To be, or not to be, that is the question.';
var bool = startsWith( str, 'To be' );
// returns true
bool = startsWith( str, 'to be' );
// returns false
By default, the function searches from the beginning of the input string
. To search from a different character index, provide a position
value (zero-based). If provided a negative position
, the start index is determined relative to the string end (pos = str.length + position
).
var str = 'Remember the story I used to tell you when you were a boy?';
var bool = startsWith( str, 'the story' );
// returns false
bool = startsWith( str, 'the story', 9 );
// returns true
bool = startsWith( str, 'you', -15 );
// returns true
If provided an empty search
string, the function always returns true
.
var str = 'beep boop';
var bool = startsWith( str, '' );
// returns true
Examples
var startsWith = require( '@stdlib/string-starts-with' );
var bool;
var str;
str = 'Fair is foul, and foul is fair, hover through fog and filthy air';
bool = startsWith( str, 'Fair' );
// returns true
bool = startsWith( str, 'fair' );
// returns false
bool = startsWith( str, 'foul', 8 );
// returns true
bool = startsWith( str, 'filthy', -10 );
// returns true
CLI
Installation
To use the module as a general utility, install the module globally
npm install -g @stdlib/string-starts-with
Usage
Usage: starts-with [options] --search=<string> [<string>]
Options:
-h, --help Print this message.
-V, --version Print the package version.
--search string Search string.
--pos int Search position.
--split sep Delimiter for stdin data. Default: '/\\r?\\n/'.
Notes
If the split separator is a regular expression, ensure that the
split
option is either properly escaped or enclosed in quotes.# Not escaped... $ echo -n