fbc: fix token pasting operator '##' to allow pasting of single '_' characters #310
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…he dynamic addition of a line continuation character ("_"), Causes the compiler to delay parsing the line continuation.This allows multiple lines of code in the input file to be combined into a single statement. For example:
Type _MAP_ENTRY
id As integer
pA As integer
End Type
#macro BEGIN_ENTRIESMAP()
Function _GetMapEntries() As _MAP_ENTRY Ptr
Static As _MAP_ENTRY _entries(0 To ...) = { ##_
#endmacro
#macro END_ENTRIESMAP()
(0, 0)}
Return @_entries(0)
End Function
#endmacro
#define _INTERFACE_ENTRY(x, y) (x, y), ##_
BEGIN_ENTRIESMAP()
_INTERFACE_ENTRY(1, 2)
_INTERFACE_ENTRY(3, 4)
_INTERFACE_ENTRY(5, 6)
END_ENTRIESMAP()
/' Compiler parsing results:
Function _GetMapEntries() As _MAP_ENTRY Ptr
Static As _MAP_ENTRY _entries(0 To ...) = { _
(1, 2), _
(3, 4), _
(5, 6), _
(0, 0)}
Return @_entries(0)
End Function
'/
…r '_' - allow multiple lines of macro expanded code to be combined into a single statement.(Skyfish)
- lex.bas - pp.bas
- previously fbc unable to handle single '_' token pasting single since in such cases the '_' is always seen as line continutation. Example: #define join1(a,b) a##_ b #define join2(a,b) a _##b #define join3(a,b) a##_##b - because '_' line continuation and '##' token pasting are handled nearly entirely in the lexer, no token checks can be made - adds lexGetLookAheadChar2( ) so that the sequence '_##' can be checked before tokenizing - plus previous commits (Skyfish) allow handling the sequence '##_' to escape the '_' character and paste it in on expansion
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This change builds on PR #309 to also allow single
'_'character token pasting.'_' token pasting since in such cases the'_'is always seen as line continuation.Example:
'_'line continuation and'##'token pasting are handled nearly entirely in the lexer, no token checks can be made'_##'can be checked before tokenizing'##_'to escape the'_'character and paste it in on expansion