2016-05-15 14:56:29 UTC
* replace the tilde in the indeterminate record syntax with VAR
* replace NONE in the extensible record syntax with NIL
The former because M2C uses the same lexer for PIM and its M2R10 subset, and tilde may be used in PIM as a synonym for NOT. The latter because it means M2C can do without any additional reserved words for both PIM and its M2R10 subset (at least for now).
However, we didn't want to have any diversion between the M2R10 specification and M2C's subset thereof. Therefore we decided to "back port" the changes into the M2R10 specification.
As a result:
(1) the use of the tilde has been completely eliminated from M2R10
(2) within the extensible record syntax NIL replaces NONE in M2R10
(3) tilde has been reserved for use by the template engine utility
This has now been updated on the wiki.
The affected productions are #15.2, #34.1, #34.2, #57 and #57.1.