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digitalmars.D.learn - Error in "Template Alias Parameter" example in the documentation

reply simendsjo <simen.endsjo pandavre.com> writes:
This example comes from http://digitalmars.com/d/2.0/template.html

int x;

template Foo(alias X)
{
    static int* p = &X;
}

void test()
{
    alias Foo!(x) bar;
    *bar.p = 3;		// set x to 3
    static int y;
    alias Foo!(y) abc;
    *abc.p = 3;		// set y to 3
}

Compiling this gives the following compiler errors on the line inside Foo:
t.d(5): Error: non-constant expression & x
t.d(5): Error: non-constant expression & y

Changing static int* to enum int* fixes the compiler errors.

Are these pages written using DDoc? Is it possible to extract and compile the
examples to
ensure they are correct? And perhaps use asserts instead of/in addition to
comments where
possible (Asserts are used many places already)?
Executable and verifiable examples could be a useful feature as plain text
documentation and
examples have a tendency to rot.
Mar 17 2011
parent Jesse Phillips <jessekphillips+D gmail.com> writes:
simendsjo Wrote:

 Are these pages written using DDoc? Is it possible to extract and compile the
examples to
 ensure they are correct? And perhaps use asserts instead of/in addition to
comments where
 possible (Asserts are used many places already)?
 Executable and verifiable examples could be a useful feature as plain text
documentation and
 examples have a tendency to rot.

There has been talk about getting Examples compiled as part of unit tests. Agreement on how to do that was not reached (Sometimes examples require a lot of setup code). This example is probably old and in need of updating, file a bug report.
Mar 17 2011