assertBoolean method
Throws a SassScriptException
if this
isn't a boolean.
Note that generally, functions should use isTruthy rather than requiring a literal boolean.
If this came from a function argument, name
is the argument name
(without the $
). It's used for error reporting.
Implementation
SassBoolean assertBoolean([String? name]) =>
throw SassScriptException("$this is not a boolean.", name);