SUB pointer and optional single ANY PTR parameter

[fxm]

Since fbc 0.90.0, calling through a procedure pointer does not fully support an optional "Any Ptr" parameter:

Code: Select all

Type t As Any Ptr

Sub test (Byval p As t = 0)
End Sub

test(0)
test()

Dim As Sub (Byval As t = 0) ptest = @test
ptest(0)
ptest()

Compiler output:
...\FBIDETEMP.bas(11) error 1: Argument count mismatch, found ')' in 'ptest()'

That compiles with any other pointer type.

[Munair]

Thanks.

[fxm]

But for me, I consider this a bug unless someone gives me the reason for why.

I wait a little your reactions before filling a bug report.

[D.J.Peters]

@fxm it's a tiny bug
but a bug is a bug :-)

The lexer has a problem if the only param are of type "any" and has a default value of "NULL"

Joshy

Code: Select all

Type TANY As any ptr

Sub test (byval first as integer=0, Byval second As TANY=0)
End Sub

test():test(1):test(,0):test(1,0)

Dim As Sub (byval first as integer=0, Byval second As TANY=0) ptest = @test
ptest() : ptest(1) : ptest(,0) : ptest(1,0)

sleep

[Munair]

No, this looks like a bug. I meant thanks for pointing it out.

[MrSwiss]

The bug seems to be in line 1 (type t, instead of Dim As ...)

Code: Select all

Dim As Any Ptr t

Sub test (Byval p As Any Ptr = 0)
End Sub

test(0)
test()

Dim As Sub (Byval As Any Ptr = 0) ptest = @test
ptest(0)    '<---- works correct to here
'ptest()    ' argument count mismatch (error 1)
Sleep

[dodicat]

It woks for function OK
The closest I can get to sub is:

Code: Select all

 

function test (Byval p As Any Ptr = 0) as sub
    print "test"
    return p
End function

test(0)
test()

Dim As function (Byval As Any Ptr = 0) as sub ptest = @test
ptest(0)   
ptest() 


#print typeof(test)


Sleep 

[St_W]

The bug seems to be in line 1 (type t, instead of Dim As ...)

Those are different things. What fxm is using is called a type alias (see https://freebasic.net/wiki/wikka.php?wa ... ypeAliases ; you may also know "typedef" from C).

@dodicat: didn't know that such syntax is even legal/possible in FB :-)
Congrats for finding that workaround. However, I wouldn't use such code in a "real" application.

[fxm]

OK dodicat.

Code: Select all

Sub test (Byval p As Any Ptr = 0)
  Print "test"
End Sub

test(0)
test()

Dim As Function (Byval As Any Ptr = 0) As Integer ptest = Cast(Any Ptr, @test)
ptest(0)
ptest()

[fxm]

Thank you all for clarifying the conditions for obtaining this compilation error that I consider a compilation bug.

Bug report filled in:
#892 Bug when default calling via a pointer to a 'Sub' defined with the only 'Any Ptr' optional parameter