Function name without () not caught

[c.haslam]

Consider:

Opt('MustDeclareVars',1)

Global $gPassword, $gSchedAr[1][2] = [['cat','2015-05-03 14:34']], $gQsched = -1, $gHolidayDates = ""
Const $kDate=2

ReportAndRemoveMissedAlarms()

Func ReportAndRemoveMissedAlarms()
    Local $missedRows = ''
    For $i = 0 to $gQsched-1
        Local $vec = StringSplit($gSchedAr[$i][$kDate],' at ',1)    ; string
        Local $date = $vec[1], $time = $vec[2]
        If $date<nowDate Then
            $missedRows &= ','&$i*100
        ElseIf $date=nowDate Then
            If $time='login' Then
                $missedRows &= ','&$i
            ElseIf $time<NowTime() Then
                $missedRows &= ','&$i
            EndIf
        EndIf
    Next
    MsgBox(0,'',NowDate)
EndFunc

Func NowDate()
    Local $ret = StringFormat('%4u-%02u-%02u',@YEAR,@MON,@MDAY)
    Return $ret
EndFunc

Func NowTime()
    Local $ret = StringFormat('%02u:%02u',@HOUR,@MIN)
    Return $ret
EndFunc

This is an excerpt from a much longer script.

I intended to write NowDate(), but didn't. The script ran OK; it reported nowDate as ''. Should AutoIt have caught this error?

 

 

 

Edited May 4, 2015 by c.haslam

[Melba23]

c.haslam,

The ability to assign function names (with no trailing parentheses) to variables has been part of AutoIt for some time - you can see an instance in the _ArrayDisplay example in the Help file. As such Au3Check does not flag up the use of a function name with no trailing parentheses as an error - the user needs to keep an eye out for that.

M23

 

[iamtheky]

 

MsgBox(0,'Func Name',NowDate())

    $date = NowDate

    MsgBox(0, 'new variable' , $date())



Func NowDate()
    Local $ret = StringFormat('%4u-%02u-%02u',@YEAR,@MON,@MDAY)
    Return $ret
EndFunc

 

new refresh is way slow, melba wins again.

Edited May 4, 2015 by boththose

[c.haslam]

Melba23,

 

Thanks for the heads-up. But why did the MsgBox show NowDate as ''? I would have expected something like 2015-05-04 .

Edited May 4, 2015 by c.haslam

[guinness]

It's like in JavaScript where functions are first class objects.

[jchd]

You passed a function-type argument to MsgBox where it expects a string. What AutoIt does in that case is convert the argument to string type and that evaluates to an empty string in your case.

#include <Date.au3>

Local $var = _NowDate
ConsoleWrite(VarGetType($var) & @LF)
$var = _NowDate()
ConsoleWrite(VarGetType($var) & @LF)

The first assignment is not an invokation of the function, while the second is.

[c.haslam]

Thank you all for your explanations. I have few suggestions:

1. I note that the Function Notes help is within Function Reference. In that this help applies to all functions, including UDFs, perhaps it should be within Language Reference.
2. In Func ... EndFunc help, I did not see mention of passing a function name (or a value containing a function name) as a parameter. Perhaps add to this help topic either the ability to pass a function name (or a value containing a function name) as a parameter , or  a link to Function Notes.
3. Perhaps add to Function Notes something like If you pass a function name to a function that expects a parameter that is not a function name (e.g. a string), your code will behave as though '' was returned.
4. Function Notes says (for v. 3.3.12.0) or return from another function. Perhaps this should read or return it from another function
5. Perhaps, if not already there, one or more examples of a function name being a parameter should be added to Function Notes.

I have a question:

1. Would it be possible for the run-time to detect when a function name is passed to a function which expects a non-function value?

I have not moved up to the latest beta. Perhaps these suggestions have already been addressed in its help.

 

...chris

Edited May 5, 2015 by c.haslam

[jchd]

Granted, Function and UserFuntion should definitely be added to the Datatypes section. This section should also mention Arrays and Maps since they are also types (check with VarGetType()) and refer to the Variables section for details. Other missing types are Keyword, Object and DllStruct.

3. Should also be mentionned in Datatype section, as you can already find a subset of the conversion rules that apply.
5. An exeample is already provided right there.

About your 1. question: it IS detected and converted as dictated by subsequent use. Again AutoIt isn't strongly typed and this is a fundamental design decision. There is no such thing as "Type mismatch" in AutoIt.