Some operators, such as and , or , and div , are written as keywords, but they are recognized as keywords only if they appear in a context where an operator is expected. The language is carefully arranged so that there is no ambiguity, and you can happily write constructs such as and or or to test whether there is an element called or an element called in your source document.
Some operator names consist of doubled keywords, such as instance of or castable as . These are recognized only if they appear as a pair. You can use whatever whitespace and comments you wish between the keywords.