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0 pointsandrewcooke14y ago0 comments

how does it square typing with macros? is it typed after macro application?

0 comments

There are different "macro stages" to allow macro application on both typed and untyped source.

so if macros can operate on typed source and/or on the typed ast tree, do they (the macros) have a type system that guarantees that they will preserve correct typing? or are types still checked agan (globally?) after applying the macro?

what i'm really asking is, is there anything "smart" about how the macro works with the type system?

VladD214y ago

Macros are expending in the typing process. In macro you can use compiler API to type some untyped AST (for example, argument of macro).

For example, "foreach" macro use compiler API to infer type of collection. This macro generate specialized code for different collection kind (array/list/IEnumerable).

VladD214y ago

For example, see implementation of "lock" macro: http://code.google.com/p/nemerle/source/browse/nemerle/trunk...

ziaw14y ago

yes, but macros can operate with typed AST too

j / k navigate · click thread line to collapse

0 comments

hi_octane14y ago

There are different "macro stages" to allow macro application on both typed and untyped source.

andrewcookeOP14y ago

what i'm really asking is, is there anything "smart" about how the macro works with the type system?

VladD214y ago

Macros are expending in the typing process. In macro you can use compiler API to type some untyped AST (for example, argument of macro).

For example, "foreach" macro use compiler API to infer type of collection. This macro generate specialized code for different collection kind (array/list/IEnumerable).

VladD214y ago

For example, see implementation of "lock" macro: http://code.google.com/p/nemerle/source/browse/nemerle/trunk...

ziaw14y ago

yes, but macros can operate with typed AST too

j / k navigate · click thread line to collapse