ILAsm syntaxes: when commands start with dot?

Question

Some ILAsm commands/directives start with dot, some not. In particular there is a pair '.try' - 'catch'. Is there a rule to explain/memorize when we use dots (without memorizing the complete list of all cases)?

Answer 1

From §II.15.4.1 Method body of the ECMA CLI spec:

The method body shall contain the instructions of a program. However, it can also contain labels, additional syntactic forms and many directives that provide additional information to ilasm and are helpful in the compilation of methods of some languages.

So, instructions are without a dot and “directives” are with a dot. I think that catch is not considered a directive on its own, because it is part of the .catch directive.