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digitalmars.D.learn - static foreach not working with this

reply Michelle Long <HappyDance321 gmail.com> writes:
static foreach(k, p; AliasSeq!(this, s))		
{{
     p.foo(); // Fails even if this line is removed
}}

this not known at compile time. replace s with this and it works! 
s is an argument which is also not known at compile 
time(generally).

Should work with this.

Just "simplifying"

this.foo();
s.foo();


(obviously more complex code)
Jan 07
parent reply Michelle Long <HappyDance321 gmail.com> writes:
On Monday, 7 January 2019 at 16:01:50 UTC, Michelle Long wrote:
 static foreach(k, p; AliasSeq!(this, s))		
 {{
     p.foo(); // Fails even if this line is removed
 }}

 this not known at compile time. replace s with this and it 
 works! s is an argument which is also not known at compile 
 time(generally).

 Should work with this.

 Just "simplifying"

 this.foo();
 s.foo();


 (obviously more complex code)
static foreach(k, p; AliasSeq!(Alias!this, s)) {{ p.foo(); // Fails even if this line is removed }}
Jan 07
next sibling parent reply Alex <sascha.orlov gmail.com> writes:
On Monday, 7 January 2019 at 16:16:57 UTC, Michelle Long wrote:
 On Monday, 7 January 2019 at 16:01:50 UTC, Michelle Long wrote:
 static foreach(k, p; AliasSeq!(this, s))		
 {{
     p.foo(); // Fails even if this line is removed
 }}

 this not known at compile time. replace s with this and it 
 works! s is an argument which is also not known at compile 
 time(generally).

 Should work with this.

 Just "simplifying"

 this.foo();
 s.foo();


 (obviously more complex code)
static foreach(k, p; AliasSeq!(Alias!this, s)) {{ p.foo(); // Fails even if this line is removed }}
referring to https://forum.dlang.org/post/aqypsijjvajybtqtmnwt forum.dlang.org Do you trying to do a recursive call from foo to itself?
Jan 07
parent Michelle Long <HappyDance321 gmail.com> writes:
On Monday, 7 January 2019 at 16:29:25 UTC, Alex wrote:
 On Monday, 7 January 2019 at 16:16:57 UTC, Michelle Long wrote:
 On Monday, 7 January 2019 at 16:01:50 UTC, Michelle Long wrote:
 static foreach(k, p; AliasSeq!(this, s))		
 {{
     p.foo(); // Fails even if this line is removed
 }}

 this not known at compile time. replace s with this and it 
 works! s is an argument which is also not known at compile 
 time(generally).

 Should work with this.

 Just "simplifying"

 this.foo();
 s.foo();


 (obviously more complex code)
static foreach(k, p; AliasSeq!(Alias!this, s)) {{ p.foo(); // Fails even if this line is removed }}
referring to https://forum.dlang.org/post/aqypsijjvajybtqtmnwt forum.dlang.org Do you trying to do a recursive call from foo to itself?
foo has nothing to do with it, as I said, removing it produces the same error['p.foo(); // Fails even if this line is removed']. I only put in something in the block because some blockhead would say something if there was nothing there like "Why are you even bothering with a static for each on an empty block? are you that stupid that you don't realize the compiler won't emit any code?".
Jan 07
prev sibling parent reply Steven Schveighoffer <schveiguy gmail.com> writes:
On 1/7/19 11:16 AM, Michelle Long wrote:
 On Monday, 7 January 2019 at 16:01:50 UTC, Michelle Long wrote:
 static foreach(k, p; AliasSeq!(this, s))
 {{
     p.foo(); // Fails even if this line is removed
 }}

 this not known at compile time. replace s with this and it works! s is 
 an argument which is also not known at compile time(generally).

 Should work with this.

 Just "simplifying"

 this.foo();
 s.foo();


 (obviously more complex code)
static foreach(k, p; AliasSeq!(Alias!this, s)) {{     p.foo(); // Fails even if this line is removed }}
To expand on Michelle's cryptic response, the second form (using `Alias!this` instead of `this`) DOES work! I think this is a bug. If the latter works, the former should. Please file at issues.dlang.org with a complete example. -Steve
Jan 07
parent Alex <sascha.orlov gmail.com> writes:
On Monday, 7 January 2019 at 16:31:49 UTC, Steven Schveighoffer 
wrote:
 On 1/7/19 11:16 AM, Michelle Long wrote:
 On Monday, 7 January 2019 at 16:01:50 UTC, Michelle Long wrote:
 [...]
static foreach(k, p; AliasSeq!(Alias!this, s)) {{     p.foo(); // Fails even if this line is removed }}
To expand on Michelle's cryptic response, the second form (using `Alias!this` instead of `this`) DOES work! I think this is a bug. If the latter works, the former should. Please file at issues.dlang.org with a complete example. -Steve
Ah, yes.
Jan 07