TALES 'string' expressions

A string: expression builds a literal string value, using optional placeholder replacement. Placeholder are indicated using either the syntax $PATH_EXPRESSION or ${PATH_EXPRESSION}, where PATH_EXPRESSION is evaluated as if it were a TALES path: expression. If the path expression body contains only alphanumeric characters, underscores and forward-slashes then the first syntax is sufficient. For expressions which require more complex characters, or spaces, then the second syntax, using braces, is required.

Literal dollar symbols may be included in the string, escaping them by doubling-them up: $$.

Otherwise, the returned value of the expression is a System.String literal created from the expression body, with replacements from the TALES context made using the placeholder expressions. Where placeholder expressions return null references, they are converted to empty strings. Where placeholder expressions return non-null values which are not System.String, they are converted using their default Object.ToString() method.