__FB_QUERY_SYMBOL__
Intrinsic define (macro) performed by the compiler, and its associated sub-macros.
Syntax:
__FB_QUERY_SYMBOL__( what, sym )
Usage:
The ./inc/fbc-int/symbol.bi header exposes internals of the fbc compiler through the built-in macro __FB_QUERY_SYMBOL__.
In addition, many convenient sub-macros with 'is' as name prefix (also defined in the file ./inc/fbc-int/symbol.bi) help the user to indirectly call the generic built-in macro __FB_QUERY_SYMBOL__:
In addition, many convenient sub-macros with 'is' as name prefix (also defined in the file ./inc/fbc-int/symbol.bi) help the user to indirectly call the generic built-in macro __FB_QUERY_SYMBOL__:
Parameters:
sym
symbol name to query
b
boolean to store the return value from the macro
XXXXX
body of the sub-macro name standing the kind of query
Description:
__FB_QUERY_SYMBOL__ is a generic built-in macro for querying fbc symbol internals.
In the file ./inc/fbc-int/symbol.bi, many convenient and specialized sub-macros with 'is' as name prefix ('isXXXXX') are also defined (where 'XXXXX' stands for the kind of query).
They help the user to indirectly call the generic built-in macro __FB_QUERY_SYMBOL__ without knowing the encoding of its first parameter and its return value, but passing the only sym parameter to those sub-macros which only return -1 (for True) or 0 (for False).
For three of the query types, convenient and specialized sub-macros are available:
In the file ./inc/fbc-int/symbol.bi, many convenient and specialized sub-macros with 'is' as name prefix ('isXXXXX') are also defined (where 'XXXXX' stands for the kind of query).
They help the user to indirectly call the generic built-in macro __FB_QUERY_SYMBOL__ without knowing the encoding of its first parameter and its return value, but passing the only sym parameter to those sub-macros which only return -1 (for True) or 0 (for False).
For three of the query types, convenient and specialized sub-macros are available:
- 'class of symbols' (like variable, constant, procedure, namespace, ...),
- 'class of data' (like integer, float, string, UDT, ...),
- 'type of data' (like boolean, byte, ubyte, short, ...).
in order to test whether a symbol matches an element of the considered family.- 'class of data' (like integer, float, string, UDT, ...),
- 'type of data' (like boolean, byte, ubyte, short, ...).
Examples:
Using convenient sub-macros from the ./inc/fbc-int/symbol.bi file (indirectly calling __FB_QUERY_SYMBOL__)
Using directly __FB_QUERY_SYMBOL__ and some declarations from the ./inc/fbc-int/symbol.bi file to output the data class of a symbol:
Using directly __FB_QUERY_SYMBOL__ and some declarations from the ./inc/fbc-int/symbol.bi file to output the typename as text, the typename as text with special characters replaced with '_', and the decorated (mangled) type name (WIP), of a symbol:
Version:#include once "fbc-int/symbol.bi"
Using FBC
Type T
i As Integer
End Type
Dim x As T
Print isUDT( T ) '' returns -1 (true)
Print isVariable( T ) '' returns 0 (false)
Print isUDT( x ) '' returns 0 (false)
Print isVariable( x ) '' returns -1 (true)
Sleep
Using FBC
Type T
i As Integer
End Type
Dim x As T
Print isUDT( T ) '' returns -1 (true)
Print isVariable( T ) '' returns 0 (false)
Print isUDT( x ) '' returns 0 (false)
Print isVariable( x ) '' returns -1 (true)
Sleep
#include once "fbc-int/symbol.bi"
Using FBC
Function dataclassToStr( ByVal classid As fbc.FB_DATACLASS ) As String
Static As ZString Ptr classnames _
( FB_DATACLASS.FB_DATACLASS_INTEGER To FB_DATACLASS.FB_DATACLASS_UDT ) _
= { @"integer", @"float", @"string", @"udt" }
Select Case classid
Case LBound(classnames) To UBound(classnames)
Return *classnames(classid)
Case Else
Return "*invalid*"
End Select
End Function
#macro show_dataclass( sym )
Scope
Var classid = __FB_QUERY_SYMBOL__( FB_QUERY_SYMBOL.dataclass, sym )
Print Left( " [" & classid & "] " & dataclassToStr(classid) + Space(16), 16 ) & ": ";
Print #sym
End Scope
#endmacro
Dim As Byte b
Dim As Double d
Dim As String s
Type T
Dim As Long l
End Type
Dim As T t1
Print "EXAMPLES OF '__FB_QUERY_SYMBOL__( FB_QUERY_SYMBOL.dataclass, sym )':"
show_dataclass( b )
show_dataclass( d )
show_dataclass( s )
show_dataclass( T )
show_dataclass( T.l )
show_dataclass( t1 )
show_dataclass( t1.l )
Sleep
Using FBC
Function dataclassToStr( ByVal classid As fbc.FB_DATACLASS ) As String
Static As ZString Ptr classnames _
( FB_DATACLASS.FB_DATACLASS_INTEGER To FB_DATACLASS.FB_DATACLASS_UDT ) _
= { @"integer", @"float", @"string", @"udt" }
Select Case classid
Case LBound(classnames) To UBound(classnames)
Return *classnames(classid)
Case Else
Return "*invalid*"
End Select
End Function
#macro show_dataclass( sym )
Scope
Var classid = __FB_QUERY_SYMBOL__( FB_QUERY_SYMBOL.dataclass, sym )
Print Left( " [" & classid & "] " & dataclassToStr(classid) + Space(16), 16 ) & ": ";
Print #sym
End Scope
#endmacro
Dim As Byte b
Dim As Double d
Dim As String s
Type T
Dim As Long l
End Type
Dim As T t1
Print "EXAMPLES OF '__FB_QUERY_SYMBOL__( FB_QUERY_SYMBOL.dataclass, sym )':"
show_dataclass( b )
show_dataclass( d )
show_dataclass( s )
show_dataclass( T )
show_dataclass( T.l )
show_dataclass( t1 )
show_dataclass( t1.l )
Sleep
#include once "fbc-int/symbol.bi"
Using FBC
Namespace NS
Type T
Dim As Const String Const Ptr Ptr pps
End Type
End Namespace
#print TypeOf(NS.T.pps)
Print "type name : " & __FB_QUOTE__( __FB_QUERY_SYMBOL__( FB_QUERY_SYMBOL.typename, NS.T.pps ) )
Print "type name id : " & __FB_QUOTE__( __FB_QUERY_SYMBOL__( FB_QUERY_SYMBOL.typenameid, NS.T.pps ) )
Print "mangled type : " & __FB_QUOTE__( __FB_QUERY_SYMBOL__( FB_QUERY_SYMBOL.mangletype, NS.T.pps ) )
Sleep
Using FBC
Namespace NS
Type T
Dim As Const String Const Ptr Ptr pps
End Type
End Namespace
#print TypeOf(NS.T.pps)
Print "type name : " & __FB_QUOTE__( __FB_QUERY_SYMBOL__( FB_QUERY_SYMBOL.typename, NS.T.pps ) )
Print "type name id : " & __FB_QUOTE__( __FB_QUERY_SYMBOL__( FB_QUERY_SYMBOL.typenameid, NS.T.pps ) )
Print "mangled type : " & __FB_QUOTE__( __FB_QUERY_SYMBOL__( FB_QUERY_SYMBOL.mangletype, NS.T.pps ) )
Sleep
- Since fbc 1.20.0 : __FB_QUERY_SYMBOL__ extended to return mangled names
- Since fbc 1.10.0
Differences from QB:
- New to FreeBASIC
Back to Intrinsic Defines
