isWhitespace

Test whether a string contains only white space characters.

Usage

var isWhitespace = require( '@stdlib/assert/is-whitespace' );

isWhitespace( value )

Tests whether a string contains only white space characters.

var bool = isWhitespace( '             ' );
// returns true

Notes

A white space character is defined as one of the 25 characters defined as a white space ("WSpace=Y","WS") character in the Unicode 9.0 character database, as well as one related white space character without the Unicode character property "WSpace=Y" (zero width non-breaking space which was deprecated as of Unicode 3.2).
For non-string values, the function returns false.

Examples

var isWhitespace = require( '@stdlib/assert/is-whitespace' );

var out = isWhitespace( '              ' );
// returns true

out = isWhitespace( '' );
// returns false

out = isWhitespace( '\\r\\n' );
// returns false

out = isWhitespace( 123 );
// returns false

CLI

Usage

Usage: is-whitespace [options] [<string>]

Options:

  -h,    --help                Print this message.
  -V,    --version             Print the package version.
         --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 $'   \nboop' | is-whitespace --split /\r?\n/

# Escaped...
$ echo -n $'   \nboop' | is-whitespace --split /\\r?\\n/

The implementation ignores trailing delimiters.

Examples

$ is-whitespace foo
false

To use as a standard stream,

$ echo -n 'foo' | is-whitespace
false

By default, when used as a standard stream, the implementation assumes newline-delimited data. To specify an alternative delimiter, set the split option.

$ echo -n '   \tbar' | is-whitespace --split '\t'
true
false