Freemarker replace string operation does not work inside a function

kavithams - Can you please share dummy text which you trying to replace and couldn't replace with function?

I tried to replace a string using your code and it worked without any issue. 

<#assign message = "this is old value" />
<#assign message = message?replace("old","new") />

${replaceVal(message)}

<#function replaceVal message>
     <#assign message = message?replace("old","new") />
     <#return message />
</#function>

I got result "this is new value". 

You can try this function here 

Maybe it needs to be case insensitive?

?replace("old", "new", "i")

TariqHussain Thank you for your reply.

I'm sharing the the code lines below. I have this code within an endpoint between; if this info helps in anyway. The null variable "surveyUrl" uninitialised is intensional so as to throw a required exception to try "replace" with.

<#attempt>

<script type= text/javascript>

window.location.href="${surveyUrl}";
</script>

<#recover>
<#assign errorMsg = .error/>
<#assign msg = errorMsg?replace('following ','FOLLOWING') />
<#--<#assign msg = msg?replace("'","\'") />-->
msg : ${msg}<br>

<br>calling function replaceVal...<br>

msg : ${replaceVal(errorMsg)}

</#attempt>

<#function replaceVal msg>

<#assign msg = msg?replace('following ','FOLLOWING') />
<#return msg />
</#function>

Using a differently named variable inside function is really strange but your solution worked great for me. Thank you.

I just remembered. inside a function use <#local var = />, instead of <#assign var =.

That shouldn't override the pre-existing variable and keep it inside the function.

You know, in case you want to use the same variable name.