有没有一种有效的方法在php中更大的正则表达式替换中运行子正则表达式替换语句

Question

I am converting a handlebars template to be reusable within the compiled page.

Sample code:

{{title}} 
<div id="desktop">
    {{#each menu}}
        <a href="{{link}}">{{name}}</a>
    {{/each}}
</div>

On the compiled page, I am wanting

Search Engines
<div id="desktop">
    <a href="https://google.com">Google</a>
    <a href="https://yahoo.com">Yahoo</a>
    <script type="text/template" id="repeatable-menu"><!--
        <a href="{{link}}">{{name}}</a>
    --></script>
</div>

I am able to get halfway there by doing a regex replace on the template before it is compiled by handlebars and get the output

Search Engines
<div id="desktop">
    <a href="https://google.com">Google</a>
    <a href="https://yahoo.com">Yahoo</a>
    <script type="text/template" id="repeatable-menu"><!--
        <a href=""></a>
    --></script>
</div>

by using the regex statement:

$templateHTML = preg_replace('/({{#each (.*?)}}(.*?){{\\/each}})/s', '$1<script type="text/template" id="repeatable-$2"><!--$3--></script>', $templateHTML, -1);

Another alternative I have come up with is to break up the handlebars statements with something like this <a href="{|{link}|}">{|{name}|}</a> but I am unsure how to do that and preserve the {{title}} variable.

would it be the wisest to run this code in a while loop until no replacements are made?

$templateHTML = preg_replace('/(<script type="text\\/template" .*?\\><!--.*?){{(.*?--\\>\\<\\/script\\>)/s', '$1{|{$2', $templateHTML, -1, $count);

Answer 1

Instead of doing it in a single preg_replace, you could use preg_replace_callback to match the pattern for the template.

Then loop through the links in the callback function.

Example snippet:

<?php

$template = '{{title}} 
<div id="desktop">
    {{#each menu}}
        <a href="{{link}}">{{name}}</a>
    {{/each}}
</div>';

$links = array(
    "Google"=>"https://google.com", 
    "Yahoo"=>"https://yahoo.com"
);

$result = preg_replace_callback(
            '/^\s*\{\{#each\s*([^{}]*)\}\}\s*^(.*?)^\s*\{\{\/each\}\}/sm',
            function ($matches) {
                $eachloopscript = $matches[0];
                $eachlooptitle  = $matches[1];
                $eachlooplines  = $matches[2];

                $scripttext = '<script type="text/template" id="repeatable-'.$eachlooptitle.'">';

                global $links;
                foreach($links as $x_key => $x_value) {
                    $temp = str_replace('{{link}}',$x_key,$eachlooplines);
                    $scripttext .= str_replace('{{name}}',$x_value,$temp);
                }

                $scripttext .= '<!--'.$eachloopscript.'--></script>';

                return $scripttext;
            }, 
            $template);

echo '<xmp>'.$result.'</xmp>';