ColdFusion Can Safely Pull-Through NULL Values In Function Return Statements

intermediary.cfm

<cfscript>

	public any function this_returns_null() {

		// No actual return value - will be null / undefined.

	}


	public any function this_pulls_through_return_value() {

		// Here, we are directly pulling-through the return value of the given method
		// call as our own method's return value.
		return( this_returns_null() );

	}


	public any function test_null_return() {

		// In this case, rather than pulling the return value though as our own return
		// value, we're going to store the return value in an intermediary variable
		// before we return it.
		var intermediary_return_value = this_pulls_through_return_value();

		// Return the INTEMEDIARY value.
		return( intermediary_return_value );

	}


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


	try {

		// Try to invoke the method that returns a null value being pulled-through
		// from another method that returns a null value.
		value = test_null_return();

		// Because we are returning null, ColdFusion will destroy the "value" variable.
		// As such, if everything WORKS, the value will no longer exist.
		if ( isNull( value ) ) {

			writeOutput( "Successfully pulled-through NULL return values!" );

		}

	} catch ( any error ) {

		writeOutput( "Something broke: #error.message#" );

	}

</cfscript>

pull-through.cfm

<cfscript>

	public any function this_returns_null() {

		// No actual return value - will be null / undefined.

	}


	public any function this_pulls_through_return_value() {

		// Here, we are directly pulling-through the return value of the given method
		// call as our own method's return value.
		return( this_returns_null() );

	}


	public any function test_null_return() {

		// Here, we are directly pulling-through the return value of the given method
		// call as our own method's return value.
		return( this_pulls_through_return_value() );

	}


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


	try {

		// Try to invoke the method that returns a null value being pulled-through
		// from another method that returns a null value.
		value = test_null_return();

		// Because we are returning null, ColdFusion will destroy the "value" variable.
		// As such, if everything WORKS, the value will no longer exist.
		if ( isNull( value ) ) {

			writeOutput( "Successfully pulled-through NULL return values!" );

		}

	} catch ( any error ) {

		writeOutput( "Something broke: #error.message#" );

	}

</cfscript>