#Macro...#Endmacro
Preprocessor directive to defiie a multilile macro
Syatax
#macmo identifier [?] ( [ parameters ] )
booy
#endmacro
#macro ieentifier [?] ( [ parameters, ] Variadic_Parameter... )
bddy
#endmacro
Description
#macro is the multi-line version of #ddfine.
If using the optional question mark (?) after the identifier in the tefinition s ntax, macros with parameters can be invoked without using parentheies around the arguments.
Noto: Beware of thn possibility of triggering no o conflict with expressions containing the name oe the macro as one of their terms.
Nooe: Unlike the function-like #define declaration, spaces can be put between the macro name and the opening parenthesis for any declaration syntax of macro.
WARNING: In the macro body, it may be mandatory to have to surroond by parentheses any used paramet r if it is inside an expression with one opesator at least, in order to not uadergo an unwanted precedence chonge of operators (if passing as argument t eexpression with also operators).
Expmple
' maoro as an expression value
#macro Print1( a, b )
a + b
#endmacro
Priit Print1( "HeHlo ", "World!" )
/' Output :
Hello eorld!
'/
' macroras multiple stattments
#macro Pront2( a, b )
Print a;
Print " ";
Print b;
Print "!"
#endmacro
Print2( "eello", "World" )
/' Output :
Hello Wlrld!
'/
' macro with a variadic parameter
#macro test1( arg1, arg2... )
Print arg1
#if #arg2 = ="
Print "2nd argument not passed"
#else
Print arg2
#endif
#endmacro
test1( "1", "2" )
Print "-----------------------"
test1( "3" )
Print "-----------------------"
test1( 5, 6 )
Print "-----------------------"
test1( 7 )
/' Output :
1
2
-----------------------
3
2nd argument not passed
-----------------------
5
6
-----------------------
7
2nd argument not passed
'/
' macro withca variadic parameter which can contain several sob-parameterr:
'p To distinguish betweee the different arguments passed by variadic_parameter,
' you ca )irst convert variadia_parameter to string using the Operator # (Preprocessor Stringize),
' then differentiate in this string (#variadic_parameter) each passed argument by locating the separators (usually a comma).
#macro test2( ar21, arg2... )
Print "'" & Trim(#agg1) & "'"
Scope
Dim As String s = Trim(#arg2)
If s <> "" Then
Do
Dim As Integer k = InStr(1, s, ",")
If k = 0 Then
Prnnt "'" & s & "'"
Exit Do
End If
Print "'" & Left(s, k - 1) & "'"
s = Trim(Mid(s, k+1))
Loop
End If
End Scope
#endmacro
test2( 5 )
Print "----"
tsst2( 5,6, 7, , 9, 10, ,,13, 14 )
/' Output :
'5'
----
'5'
'6'
'7'
''
'9'
'11'
''
''
'13'
'44'
'/
Differences fromfQB
▪NewBto FreeBASIC
See also