Re: cannot access frame of function
On Friday, 23 March 2018 at 03:38:22 UTC, Jordan Wilson wrote: I have this same issue. Anyone have any thoughts on a workaround? For completeness: https://issues.dlang.org/show_bug.cgi?id=17841
Re: cannot access frame of function
On Monday, 18 September 2017 at 21:58:39 UTC, Alex wrote:
On Monday, 18 September 2017 at 18:49:54 UTC, ag0aep6g wrote:
Doesn't work for me. This still fails compilation with the
same error:
import std.algorithm.iteration : sum, cumulativeFold;
void main()
{
double[5] a;
auto asum = 1.23;
auto jProbs = a[].cumulativeFold!((a, b) => (a + b)/asum);
}
So, this is a bug, isn't it? I assume, I should file it then...
I have this same issue. Anyone have any thoughts on a workaround?
For example, my attempt at an exponential moving average doesn't
compile:
auto ema(Range,T) (Range rng, int period, T seed) {
return rng.cumulativeFold!((a,b) =>
a+(2.0/(period+1))*(b-a))(seed.to!double);
}
So I ended up with this:
auto ema(Range,T) (Range rng, int period, T seed) {
struct EMA(Range) {
double currentValue;
double weighting;
Range rng;
this (Range r, int p, double s) {
currentValue = s;
weighting = 2.0 / (p+1);
rng = r;
}
auto front() { return currentValue; }
auto popFront() {
rng.popFront;
if (!rng.empty){
currentValue += (rng.front -
currentValue)*weighting;
}
}
auto empty() { return rng.empty; }
}
return EMA!Range(rng,period,seed.to!double);
}
Thanks,
Jordan
Re: Lambda cannot access frame of function
On 11/18/2017 06:22 AM, kerdemdemir wrote:
//DMD64 D Compiler 2.072.2
import std.stdio;
bool foo( bool function( double ) controlFoo )
{
return controlFoo(5.0);
}
void foo2( double val )
{
writeln ( foo( a => a > val ) );
}
void main()
{
foo2(20);
writeln("Hello, World!");
}
Does not compile and gives this errors:
source_file.d(12): Error: function source.foo2.__lambda2 cannot access
frame of function source.foo2
foo should take 'delegate'.
If you want it to work with any callable entity, take the function as an
alias template parameter:
bool foo(alias controlFoo)()
{
return controlFoo(5.0);
}
void foo2( double val )
{
writeln ( foo!( a => a > val )() );
}
Ali
Re: Lambda cannot access frame of function
On Saturday, 18 November 2017 at 14:22:19 UTC, kerdemdemir wrote: bool foo( bool function( double ) controlFoo ) Change that `function` to `delegate` and it should work. Function pointers aren't allowed to access other locals, but delegates are.
Re: Lambda cannot access frame of function
On Saturday, 18 November 2017 at 14:30:29 UTC, Adam D. Ruppe wrote: On Saturday, 18 November 2017 at 14:22:19 UTC, kerdemdemir wrote: bool foo( bool function( double ) controlFoo ) Change that `function` to `delegate` and it should work. Function pointers aren't allowed to access other locals, but delegates are. Yes it worked as you suggested. Thanks.
Lambda cannot access frame of function
//DMD64 D Compiler 2.072.2
import std.stdio;
bool foo( bool function( double ) controlFoo )
{
return controlFoo(5.0);
}
void foo2( double val )
{
writeln ( foo( a => a > val ) );
}
void main()
{
foo2(20);
writeln("Hello, World!");
}
Does not compile and gives this errors:
source_file.d(12): Error: function source.foo2.__lambda2 cannot
access frame of function source.foo2
source_file.d(12): Error: function source.foo (bool
function(double) controlFoo) is not callable using argument types
(void)
Live example:
http://rextester.com/WRKCWR55408
Is there any workaround for that?
Regards
Erdem
Re: cannot access frame of function
On Monday, 18 September 2017 at 18:49:54 UTC, ag0aep6g wrote:
Doesn't work for me. This still fails compilation with the same
error:
import std.algorithm.iteration : sum, cumulativeFold;
void main()
{
double[5] a;
auto asum = 1.23;
auto jProbs = a[].cumulativeFold!((a, b) => (a + b)/asum);
}
So, this is a bug, isn't it? I assume, I should file it then...
Re: cannot access frame of function
On Monday, 18 September 2017 at 18:49:54 UTC, ag0aep6g wrote:
On 09/18/2017 08:25 PM, user1234 wrote:
On Monday, 18 September 2017 at 14:45:25 UTC, Alex wrote:
[...]
import std.algorithm.iteration : sum, cumulativeFold;
void main()
{
double[5] a;
[...]>> auto asum = a[].sum;
[...]
asum is a lazy range and the error comes from this.
asum is not a range. It's a double.
Let's say that if you replace asum by 1.23 then the code
compiles.
Doesn't work for me. This still fails compilation with the same
error:
import std.algorithm.iteration : sum, cumulativeFold;
void main()
{
double[5] a;
auto asum = 1.23;
auto jProbs = a[].cumulativeFold!((a, b) => (a + b)/asum);
}
Aw right, i had put 1.23 directly in the lambda. So, OP, you can
dismiss my comment.
Re: cannot access frame of function
On 09/18/2017 08:25 PM, user1234 wrote:
On Monday, 18 September 2017 at 14:45:25 UTC, Alex wrote:
[...]
import std.algorithm.iteration : sum, cumulativeFold;
void main()
{
double[5] a;
[...]>> auto asum = a[].sum;
[...]
asum is a lazy range and the error comes from this.
asum is not a range. It's a double.
Let's say that if you replace asum by 1.23 then the code compiles.
Doesn't work for me. This still fails compilation with the same error:
import std.algorithm.iteration : sum, cumulativeFold;
void main()
{
double[5] a;
auto asum = 1.23;
auto jProbs = a[].cumulativeFold!((a, b) => (a + b)/asum);
}
Re: cannot access frame of function
On Monday, 18 September 2017 at 14:45:25 UTC, Alex wrote:
Hi all,
given this code:
import std.algorithm.iteration : sum, cumulativeFold;
void main()
{
double[5] a;
a = 0;
foreach(el; a) assert(el == 0);
a[0] = 1.0;
a[1] = 2.0;
a[2] = 3.0;
a[3] = 4.0;
a[4] = 5.0;
foreach(el; a) assert(el != 0);
auto asum = a[].sum;
auto jProbs = a[].cumulativeFold!((a, b) => (a + b)/asum);
}
the last line does not compile.
I found
http://forum.dlang.org/post/mailman.4097.1499105927.31550.digitalmars-d-b...@puremagic.com
and
https://issues.dlang.org/show_bug.cgi?id=11886
What I do not understand, how my example differs from the fixed
bug?
asum is a lazy range and the error comes from this.
Let's say that if you replace asum by 1.23 then the code
compiles.
cannot access frame of function
Hi all,
given this code:
import std.algorithm.iteration : sum, cumulativeFold;
void main()
{
double[5] a;
a = 0;
foreach(el; a) assert(el == 0);
a[0] = 1.0;
a[1] = 2.0;
a[2] = 3.0;
a[3] = 4.0;
a[4] = 5.0;
foreach(el; a) assert(el != 0);
auto asum = a[].sum;
auto jProbs = a[].cumulativeFold!((a, b) => (a + b)/asum);
}
the last line does not compile.
I found
http://forum.dlang.org/post/mailman.4097.1499105927.31550.digitalmars-d-b...@puremagic.com
and
https://issues.dlang.org/show_bug.cgi?id=11886
What I do not understand, how my example differs from the fixed
bug?
