用clearsilver宏实现的replace

RT，用clearsilver宏实现的replace，缺点是宏不能嵌套，类似只能调用一次的函数，cs这个东东，需要扩展的东西太多了。

<?cs def:replace(val, f, t) ?>
    <?cs set:index=string.find(val, f)?>

    <?cs if:index>-1 ?>
        <?cs set:subLen=string.length(f) ?>
        <?cs set:begin=string.slice(val, 0, index) ?>

        <?cs set:end=string.slice(val, 0+subLen+index, string.length(val))?>
        <?cs set:val=begin+t+end?>

        <?cs if:string.find(val, f)>-1 ?>
            <?cs call:replace(val, f, t)?>
        <?cs else?>
            <?cs var:val?>
        <?cs /if?>
    <?cs else?>
        <?cs var:val?>
    <?cs /if?>
<?cs /def?>

<?cs def:strWarp2br(val)?>
 <?cs if:string.find(val, "\\r\\n")>-1?>
  <?cs call:replace(val, "\r\n", "x<br/>") ?>
 <?cs elif:string.find(val, "\\n")>-1?>
  <?cs call:replace(val, "\n", "y<br/>") ?>
    <?cs elif:string.find(val, "\\r")>-1?>
  <?cs call:replace(val, "\r", "z<br/>") ?>
 <?cs else?> 
        <?cs var:val?>
 <?cs /if?>
<?cs /def?>