codePointAt
Return a Unicode code point from a string at a specified position.
Usage
var codePointAt = require( '@stdlib/string/code-point-at' );
codePointAt( string, position[, backward] )
Returns a Unicode code point from a string at a specified position.
var out = codePointAt( 'last man standing', 4 );
// returns 32
The function supports providing a backward argument for performing backward iteration for low surrogates.
var out = codePointAt( '๐ท', 1, true );
// returns 127799
The function supports providing a negative position.
var out = codePointAt( 'last man standing', -13 );
// returns 32
Notes
This function differs from String.prototype.codePointAt in the following ways:
- The function supports providing a negative
position. If provided a negativeposition, the function determines the string position relative to the end of the string. - The function supports providing a
backwardargument for performing backward iteration for low surrogates.String.prototype.codePointAtsimply returns the low surrogate value if no UTF-16 surrogate pair begins at the specified position. If invoked withbackwardset totrue, this function will return the code point after aggregating with the preceding high surrogate, if the specified position does not mark the start of a surrogate pair. - The function raises an exception if provided a
positionwhich exceeds the bounds of the input string.
Examples
var codePointAt = require( '@stdlib/string/code-point-at' );
var v = codePointAt( 'last man standing', 4 );
// returns 32
v = codePointAt( 'presidential election', 8, true );
// returns 116
v = codePointAt( 'เค
เคจเฅเคเฅเคเฅเคฆ', 2 );
// returns 2369
v = codePointAt( '๐ท', 1, true );
// returns 127799
CLI
Usage
Usage: code-point-at [options] --pos=<index> [<string>]
Options:
-h, --help Print this message.
-V, --version Print the package version.
-b, --backward Backward iteration for low surrogates.
--pos index Position in string.
Examples
$ code-point-at --pos=2 เค
เคจเฅเคเฅเคเฅเคฆ
2369
To use as a standard stream,
$ echo -n 'เค
เคจเฅเคเฅเคเฅเคฆ' | code-point-at --pos=2
2369