Search code examples
grailsgrails-2.0gsp

Grails : Difference between \${} and ${}

Can someone tell me the difference between :

<g:if test="${foo.bar}">

and

<g:if test="\${foo.bar}">

A real exemple of the use of "\" before the "$" is : 

<g:if test="\${flash.message}">

Thank you.

Solution

  • \${...} will put a literal dollar-brace into the output rather than evaluating the contents as an expression. I rarely have need to use this in a normal GSP but it's very common in scaffolding templates where the template engine uses the same ${} syntax for its own generation-time expressions as the generated GSP uses at runtime - so you need \${} in the scaffolding template to generate expressions in the GSP which will then be evaluated for real at runtime when the page is rendered.