• Nrgyzer <nrgyzer googlemail.com> Jan 12 2010

Nrgyzer <nrgyzer googlemail.com> writes:

dsimcha Wrote:

 == Quote from Nrgyzer (nrgyzer googlemail.com)'s article
 Hello everyone,
 I currently try to create a structure with a construtor, but I always get the


 Error: Foo.this constructors are only for class definitions
 Error: constructor lisim.lsResult.lsResult.this special member functions not


 By compiling the follwing code:
 struct Foo {
     int len;
     bool len_done;
     const char* str;
     int length()
     {   if (!len_done)
         {   len = strlen(str);
 	    len_done = true;
         }
 	return len;
     }
     this(char* str) { this.str = str; }
 }
 const Foo f = Foo("hello");
 bar(f.length);
 I found that source on


 source is for d2 and not for d1 but does d1 support similar operations (or is
 there no support for struct-constructors)?
 Thanks in advance :)


 Struct constructors are D2 only.  That said, you can fake them in D1 by
 overloading static opCall:
 
 struct Foo {
     uint field;
 
     static Foo opCall(SomeType someArgument) {
         Foo foo;
 
         // Do stuff.
         foo.field = someValue;
         return foo;
     }
 }
 
 auto foo = Foo(someArgument);


Thanks - that solution works great :)