Cannot escape String in a filter value

I have to filter a file. The value to inject to the file is foo/${name}. Thus in my resource I have @something@ and in my filter I would like to have something=foo/${name}
I tried to use the escapeString option () and added in my filter I used : something=foo/\${name}
I tested with various syntaxes and escape characters but it doesn't work.
escapeString can be used to protect special characters in resources but not in filters. In filters properties are always resolved.