Php 如何用变量动态缝合模板？

我试图让用户定义要传递到字符串中的值

如何在不使用eval（）或静态定义所有变量的情况下，用模板动态缝合一些变量

我正在寻找一个小脚印解决方案。不包括整个模板引擎或库

<?php

// Create a template
  $tpl = " ... {$var['a']} ... "; // User defined content

// State variables
  $var = [
    'a' => 1,
    'b' => 2,
  ];

// Stitch
  echo $tpl;

---

只需更改替换格式：

<?php

$tpl = "Dear @name@, I would love to come to @location@."; 

$subs =
[
    '@name@'     => 'Julian',
    '@location@' => 'Freetown'
];    

echo strtr($tpl, $subs);

或者，围绕strtr的包装器：

function template($template_str, array $vars) {
    foreach($vars as $k => $v)
        $substitutes['@'.$k.'@'] = $v;
    return strtr($template_str, $substitutes);
}

$tpl = "Dear @name@, I would love to come to @location@."; 

$subs = [
    'name'     => 'Julian',
    'location' => 'Freetown'
];

echo template($tpl, $subs);

支持递归数组是什么意思？感谢您尝试回答这个问题。此解决方案不考虑递归数组。@tim，在您的问题中解释您希望如何处理它们。这还不清楚。
Dear Julian, I would love to come to Freetown.

function template($template_str, array $vars) {
    foreach($vars as $k => $v)
        $substitutes['@'.$k.'@'] = $v;
    return strtr($template_str, $substitutes);
}

$tpl = "Dear @name@, I would love to come to @location@."; 

$subs = [
    'name'     => 'Julian',
    'location' => 'Freetown'
];

echo template($tpl, $subs);