fix Issue 481 - Letting compiler determine length for fixed-length ar…

…rays
dlang · Jan 29, 2015 · 42b7679 · 42b7679
1 parent 7c70d76
commit 42b7679
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Showing 2 changed files with 45 additions and 21 deletions.
diff --git a/declaration.dd b/declaration.dd
@@ -136,6 +136,15 @@ $(GNAME BasicType2X):
     $(D delegate) $(GLINK2 function, Parameters) $(GLINK2 function, MemberFunctionAttributes)$(OPT)
     $(D function) $(GLINK2 function, Parameters) $(GLINK2 function, FunctionAttributes)$(OPT)
 
+$(GNAME BasicType3):
+    $(GLINK BasicType3X) $(GLINK BasicType3)$(OPT)
+
+$(GNAME BasicType3X):
+    $(D *)
+    $(D [ ])
+    $(D [) $(VEXPRESSION) $(D ])
+    $(D [) $(GLINK Type) $(D ])
+
 $(GNAME IdentifierList):
     $(I Identifier)
     $(I Identifier) $(D .) $(I IdentifierList)
@@ -276,45 +285,52 @@ $(H3 $(LEGACY_LNAME2 AutoDeclaration, auto-declaration, Implicit Type Inference)
 
 $(GRAMMAR
 $(GNAME AutoDeclaration):
-    $(GLINK StorageClasses) $(I AutoDeclarationX) $(D ;)
+    $(GLINK StorageClasses) $(GLINK BasicType3)$(OPT) $(I AutoDeclarationX) $(D ;)
 
 $(GNAME AutoDeclarationX):
     $(I Identifier) $(GLINK2 template, TemplateParameters)$(OPT) $(D =) $(GLINK Initializer)
     $(I AutoDeclarationX) $(D ,) $(I Identifier) $(GLINK2 template, TemplateParameters)$(OPT) $(D =) $(GLINK Initializer)
 )
 
-        $(P If a declaration starts with a $(I StorageClass) and has
+    $(P If a declaration starts with a $(I StorageClass) and has
         a $(I NonVoidInitializer) from which the type can be inferred,
         the type on the declaration can be omitted.
-        )
 
-----------
-static x = 3;      // x is type int
-auto y = 4u;       // y is type uint
+        ----------
+        static x = 3;      // x is type int
+        auto y = 4u;       // y is type uint
 
-auto s = "string"; // s is type immutable(char)[]
+        auto s = "string"; // s is type immutable(char)[]
 
-class C { ... }
+        class C { ... }
 
-auto c = new C();  // c is a handle to an instance of class C
-----------
+        auto c = new C();  // c is a handle to an instance of class C
+        ----------
+    )
 
-        $(P The $(I NonVoidInitializer) cannot contain forward references
+    $(P The $(I NonVoidInitializer) cannot contain forward references
         (this restriction may be removed in the future).
         The implicitly inferred type is statically bound
         to the declaration at compile time, not run time.
-        )
-
-        $(P An $(GLINK2 expression, ArrayLiteral)
-        is inferred to be a dynamic array
-        type rather than a static array:)
+    )
 
----
-auto v = ["hello", "world"]; // type is string[], not string[2]
----
+    $(P An $(GLINK2 expression, ArrayLiteral) is inferred to be a dynamic array
+        type rather than a static array:
 
+        ---
+        auto v = ["hello", "world"]; // type is string[], not string[2]
+        ---
+    )
 
+    $(P $(I AutoDeclaration) can restrict the inferred type partially, by using
+        $(GLINK BasicType3).
 
+        ---
+        auto[$] a = ["hello", "world"]; // type is string[2]
+        const[] b = [1, 2];             // type is const(int)[]
+        immutable* c = new int(3);      // type is immutable(int)*
+        ---
+    )
 
 $(H3 $(LNAME2 alias, Alias Declarations))
 
@@ -484,7 +500,6 @@ extern extern(C) int bar; // variable allocated outside this module with C linka
                           // (e.g. in a statically linked C library or another module)
 ---------------
 
-
 $(H3 $(LNAME2 typeof, $(D typeof)))
 
 $(GRAMMAR

diff --git a/grammar.dd b/grammar.dd
@@ -67,6 +67,15 @@ $(GNAME BasicType2X):
     $(D delegate) $(GLINK Parameters) $(GLINK MemberFunctionAttributes)$(OPT)
     $(D function) $(GLINK Parameters) $(GLINK FunctionAttributes)$(OPT)
 
+$(GNAME BasicType3):
+    $(GLINK BasicType3X) $(GLINK BasicType3)$(OPT)
+
+$(GNAME BasicType3X):
+    $(D *)
+    $(D [ ])
+    $(D [) $(VEXPRESSION) $(D ])
+    $(D [) $(GLINK Type) $(D ])
+
 $(GNAME IdentifierList):
     $(I Identifier)
     $(I Identifier) $(D .) $(I IdentifierList)
@@ -1014,7 +1023,7 @@ $(GNAME AliasDeclarationX):
 
 $(GRAMMAR
 $(GNAME AutoDeclaration):
-    $(GLINK StorageClasses) $(I AutoDeclarationX) $(D ;)
+    $(GLINK StorageClasses) $(GLINK BasicType3)$(OPT) $(I AutoDeclarationX) $(D ;)
 
 $(GNAME AutoDeclarationX):
     $(I Identifier) $(GLINK TemplateParameters)$(OPT) $(D =) $(GLINK Initializer)