Go equivalent to __FILE__ & __LINE__ ???

[Valentin Kasas]

Hi,

Is there, or will there be a way to know on which line of a source
file is written an arbitrary instruction, such as __FILE__ and
__LINE__ macros in C/C++ ?
I suppose that if there was such a way, the standard "log" package
would use it. I'm aware that Go does not and will certainly never have
a standard preprocessor, for the sake of compiling speed but, these
informations are already known by the compiler, as we can see
(hopefuly) when doing compilation errors.
I'm writing a /true/ logger inspired of the log4j I daily use, but
without thes informations, a logger is quite useless...


Regards

Vil-1

[Valentin Kasas]

Damn !

Done things in the wrong order : ask my question and then search in
the groups ...
The answer is runtime.Caller() (which may be a little slower than
__FILE__ and __LINE__).

sorry

[Cory Mainwaring]

Slower: Probably
A Macro: No
Speedy Compile Time: Yes

[Jessta]

On Tue, Sep 14, 2010 at 2:33 AM, Valentin Kasas
<valenti...@gmail.com> wrote:
> Hi,
>
> Is there, or will there be a way to know on which line of a source
> file is written an arbitrary instruction, such as __FILE__ and
> __LINE__ macros in C/C++ ?

http://golang.org/pkg/runtime/#Caller

> I suppose that if there was such a way, the standard "log" package
> would use it. I'm aware that Go does not and will certainly never have
> a standard preprocessor, for the sake of compiling speed but, these
> informations are already known by the compiler, as we can see
> (hopefuly) when doing compilation errors.
> I'm writing a /true/ logger inspired of the log4j I daily use, but
> without thes informations, a logger is quite useless...

http://code.google.com/p/log4go/

- jessta
--
=====================
http://jessta.id.au

[Rob 'Commander' Pike]

The standard log package does use it. The predeclared functions in
log do not, but you can create new Loggers that will print source
information if you use the Llongfile or Lshortfile flags to New().

-rob