sample-utterances.php

<?php
// Quick utterance generator for Alexa Skills Kit.
// Define utterance templates below, then set up token variants as arrays below that.

// Tokenized utterances
$utterances = array(
	'Nearest for the {closest} {car}',
	'Nearest where the {closest} {car} is',
	'Nearest where is the {closest} {car}',
	"Nearest where's the {closest} {car}",

	'ReserveNearest to {reserve} me the {closest} {car}',
	'ReserveNearest to {reserve} the {closest} {car}',
);

// Token variants, variables named after the tokens used above
$closest = array( 'nearest', 'closest' );
$car     = array( 'car', 'vehicle' );
$reserve = array( 'reserve', 'book', 'get' );

// Take an array of strings, and replace a token with its variants in it
function replace_token_variants( $strings, $token, $variants ) {
	$out = array();
	foreach ( $strings as $string ) {
		foreach ( $variants as $variant ) {
			$out[] = str_replace( '{' . $token . '}', $variant, $string );
		}
	}
	return $out;
}

$out = array();
foreach ( $utterances as $utterance ) {
	preg_match_all( '/({([^}]+)})/', $utterance, $tokens );
	$utter_variations = array( $utterance );
	for ( $n = 0; $n < count( $tokens[2] ); $n++ ) {
		$utter_variations = replace_token_variants( $utter_variations, $tokens[2][$n], ${$tokens[2][$n]} );
	}
	$out = array_merge( $out, $utter_variations );
}

echo implode( $out, "\n" ) . "\n";