How to escape identifiers in Boo?

Question

If I have an identifier with a same name as existing keyword, how do I escape it?

hmm, I'm using boo in production about 2 years and never had such a question)) just googled and found nothing. — Sergey Mirvoda, Dec 20 '09 at 20:56

score 1 · Accepted Answer · answered Dec 21 '09 at 15:52

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That's what I found (and this is probably the final answer):

It is possible to use @ as a prefix in identifier names. However, by default it creates a different identifier (@a != a).
Since @ is allowed, it is possible to add a new compiler step to the pipeline that will do TrimStart('@') on all identifiers. It works ok, you will just have to remember all types of things that have names.
If you are using Rhino.DSL, it has a UseSymbols step that converts @a into 'a', which had confused me a lot (I was working with project that included this step by default).

answered Dec 21 '09 at 15:52

Andrey Shchekin

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and how that work?? how code like that can be produced to AST? ''class = "Hello I'm keyword"'' yes you can wrote @class, but it is _not_ a keyword. Also you should be able do than in different levels of a type i.e. fields, parameters, properties, methods etc. It's not an easy task )) – Sergey Mirvoda Dec 21 '09 at 17:31
also you should check that a = "Hello" @a = "Hello" after your step you can get non uniq names – Sergey Mirvoda Dec 21 '09 at 17:33
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_yes you can wrote @class, but it is not a keyword_ -- well, the difference is not obvious when you stay inside Boo, but consider a calling application in some other language where, for example, 'def' is not a keyword. In this case, difference between 'def _def()' and 'def @def()' is that it would be callable as 'x._def()' in the first case , and 'x.def()' in the second. – Andrey Shchekin Dec 21 '09 at 17:43
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as for the unique names, I know it, but it is the same as C# does it, so I (and other users) am quite accustomed to this. – Andrey Shchekin Dec 21 '09 at 17:44

score 0 · Answer 2 · edited May 23 '17 at 11:47

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I don't think anything like the C# @ prefix is implemented in Boo... but I'm pretty sure it could be achieved by inserting a custom compiler step to the beginning of the compiler pipeline.

edited May 23 '17 at 11:47

Community

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answered Dec 21 '09 at 02:15

Mauricio Scheffer

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I think it is not possible at all. compiler steps operates on AST. but which AST will be produced for such a code class = 'Hello' – Sergey Mirvoda Dec 21 '09 at 10:02
Added my finding as an answer. – Andrey Shchekin Dec 21 '09 at 15:52
so it *was* possible with a compiler step after all – Mauricio Scheffer Dec 21 '09 at 16:08
yes, and I am ok with compiler steps, but I was hoping that there is something that works out of the box. – Andrey Shchekin Dec 21 '09 at 16:33

How to escape identifiers in Boo?

2 Answers2