Something like MVC

some_foobar_controller.php

<?php
function get_some_foo(){
	return array( 'foo_one', 'foo_two', 'foo_three' );
}

function get_some_bar(){
	return array( 'bar_one', 'bar_two', 'bar_three' );
}

function some_view( $the_array ){
	
	$output = '<ul>';
	
	foreach( $the_array as $element )
		$output .= sprintf( '<li>%s</li>', $element );
	
	$output .= '</ul>';
	
	return $output;
}

function some_storage( $the_array ){
	
	$filename = 'storage_view.txt';
	$filehandle = fopen( $filename, 'w+' );
	
	if( $filehandle ){
		$file_output = some_view( $the_array );
		fwrite( $filehandle, $file_output );
		fclose( $filehandle );
		
		// on success
		return true;
	} else {
		// on error
		return false;
	}
}

function some_controller( $get_what, $do_what ){

	// check args
	$get_what = 'get_some_' . $get_what;
	if( ! in_array( $get_what, array( 'get_some_foo', 'get_some_bar' ) ) )
		$get_what = 'get_some_foo';
		
	$do_what = 'some_' . $do_what;
	if( ! in_array( $do_what, array( 'some_view', 'some_storage' ) ) )
		$do_what = 'some_view';
		
	// get the array
	$the_array = call_user_func( $get_what );

	// do something with the array
	$output = call_user_func( $do_what, $the_array );

	$success = false;
	
	// $output is not false (no error) and it is a string, we can print $output
	// we complete the job (creating a list) successfully, store this state in $success
	if( false !== $output && is_string( $output ) ){
		echo $output;
		$success = true;
	}
	// if $output is true but not a string, the job (storing the output) was successfully done.
	// on error, $output is false. we can store this state (true or false) in $success
	else {
		$success = $output;
	}
	
	/*
	 * do something with $success
	 * 
	 */
	var_dump( $success );
}

some_controller( 'foo', 'view' );
some_controller( 'bar', 'view' );
some_controller( 'bar', 'storage' );