The day past, an exterior API name that I used to be making failed as a result of one of the most values that I used to be posting contained a trailing “0 width house” persona (u200b). The worth in query was once being passed-through ColdFusion’s local trim() serve as; which was once obviously no longer doing away with this whitespace persona. As such, it passed off to me that I did not in point of fact know which characters are (and don’t seem to be) treated by way of the trim() serve as. And so, I sought after to run a take a look at.

Some of the issues that I love about Lucee CFML is that all the supply code is posted proper there on GitHub. So, if I need to know the way one thing is operating beneath the hood, I will be able to simply cross have a look at it. Once we have a look at Lucee’s implementation of the trim() serve as, we will see that it’s handing management off to Java’s String.trim() way. And, Java’s String.trim() gets rid of all ASCII characters from u0000 as much as (and together with) u0020 (the gap persona).

In fact, since Adobe ColdFusion’s code is closed-source, we will’t know what it’s doing. We will handiest take a look at it. And, do that, I am gathering all the “typical” whitespace characters and the non-standard whitespace characters (that I recognized in my text-normalization part) and I am looping over them to peer in the event that they live to tell the tale a decision to trim():

<cfscript>

	testCharacters = [
		// Standard "whitespace" charaters.
		hexToChar( "0009" ), // Tab.
		hexToChar( "0010" ), // Line Break.
		hexToChar( "0013" ), // Carriage Return.
		hexToChar( "0020" ), // Space.

		// Non-stanard "whitespace" characters.
		hexToChar( "00a0" ), // No-Break Space.
		hexToChar( "2000" ), // En Quad (space that is one en wide).
		hexToChar( "2001" ), // Em Quad (space that is one em wide).
		hexToChar( "2002" ), // En Space.
		hexToChar( "2003" ), // Em Space.
		hexToChar( "2004" ), // Thic Space.
		hexToChar( "2005" ), // Mid Space.
		hexToChar( "2006" ), // Six-Per-Em Space.
		hexToChar( "2007" ), // Figure Space.
		hexToChar( "2008" ), // Punctuation Space.
		hexToChar( "2009" ), // Thin Space.
		hexToChar( "200a" ), // Hair Space.
		hexToChar( "200b" ), // Zero Width Space.
		hexToChar( "2028" ), // Line Separator.
		hexToChar( "2029" ), // Paragraph Separator.
		hexToChar( "202f" ), // Narrow No-Break Space.
		hexToChar( "feff" )  // Zero Width No-Break Space.
	];

	// For each and every take a look at whitespace persona, let's examine if it survives a trim() name.
	for ( c in testCharacters ) {

		writeOutput( len( trim( c ) ) );
		writeOutput( " , " );

	}

	// ------------------------------------------------------------------------------- //
	// ------------------------------------------------------------------------------- //

	/**
	* I convert the given hex-encoded persona to an ASCII persona.
	*/
	public string serve as hexToChar( required string hexEncoded ) {

		go back( chr( inputBaseN( hexEncoded, 16 ) ) );

	}

</cfscript>

As you’ll be able to see, I get started with our 4 maximum not unusual control-characters and areas; after which, I observe with various different unusual whitespace characters. Once we run this code in both Lucee CFML or Adobe ColdFusion, we get the similar output:

0, 0, 0, 0,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1

As you’ll be able to see, the primary 4 take a look at characters (Tab, Line-Spoil, Carriage Go back, Area) had been all got rid of by way of the trim() serve as – which fits what Java’s String.trim() serve as is documented to do. And, all the different unusual whitespace characters stay. As such, I feel it might be truthful to think that Adobe ColdFusion’s trim() serve as is most likely additionally handing management off to Java’s String.trim() implementation. Because of this that each CFML engines handiest take away characters u0000 as much as and together with u0020 of their trim() serve as implementations.

Wish to use code from this put up?
Take a look at the license.