Changes between Version 7 and Version 8 of Language

Timestamp:

06/24/09 09:43:57 (4 years ago)

Author:

benl (IP: 150.203.160.45)

Comment:

--

Language

@@ -14 +14 @@
 Modules start with an optional module identifier, followed by a list of export and import declarations. Export declarations must come before import declarations. 
 
+Although we use semicolons as terminators instead of separators, in all cases the parser will accept a missing semicolon before a closing brace.
+
 [[br]]
 
@@ -21 +23 @@
     ::= export  Var
      |  export type  Con
+     |  export region  RVar
+     |  export effect  ECon
+     |  export class   Con 
 }}}
 
@@ -90 +95 @@
 }}}
 
-Sets the kind of an abstract type constructor.
+Sets the kind of an abstract value type constructor.
 
 [[br]]
@@ -150 +155 @@
 }}}
 
+[[br]]
+
+
+== !EffectDecl ==
+
+{{{
+EffectDecl 
+    ::=  effect  ECon  ::  Kind  
+}}}
+
+Defines a new effect constructor and sets its kind. The result kind of the constructor must be !.
+
+Inference involving effect constructors of kinds other than {{{!}}} and {{{(% -> !)}}} is not well tested #89.
+
+[[br]]
+
+== !RegionDecl ==
+
+{{{
+RegionDecl
+    ::=  region  RVar  (:-  TyConstraint  ,TyConstraint*)?
+}}}
+
+Defines a top-level (global) region. 
+
+Although explicitly binding top-level region variables is not nessesary, it can be useful to define the constraints on a global region in a single place in the source file, instead of trying to repeat them in each type signature that uses it. For example:
+
+{{{
+region %r :- Const %r
+
+pi :: Float %r
+pi = 3.1415926535
+
+e :: Float %r
+e = 2.71828183
+}}}
+
+[[br]]
+
+== !ClassDecl ==
+
+{{{
+ClassDecl
+    ::=  class  Con  ::  Kind                             -- abstract class constraint
+     |   class  Con  TyVar+  where  {  TypeSig;+  }       -- value type class definition
+}}}
+
+The return kind of abstract class constraints must be {{{+}}}. We don't yet support default instances in type class declarations #90.