MacroDef::eAppendStat MacroDef::AppendMacroExpansion
(TextStream & text)
{
char c;
bool stat;
while (text.Consume(c))
{
if ('%' == c)
{
if (text.Expect ("%"))
{
// escape of '%' character: that's OK
_definition.Append (c);
_definition.Append (c);
continue;
}
int argIdx = 0;
for (int digitCount = 0; digitCount < 2; digitCount++)
{
stat = text.Consume(c);
if (! stat)
{
return kAppendBadArg;
}
if ((c >= '0') && (c <= '9'))
{
// valid arg values
if (0 == digitCount)
{
_definition.Append ('%');
}
_definition.Append (c);
argIdx = argIdx*10 + (c - '0');
if (argIdx > _numArgs)
{
return kAppendArgRange;
}
continue;
}
else
{
return kAppendBadArg;
}
}
}
else
{
_definition.Append (c);
}
}
return kAppendNoError;
}
MacroDef::eInvokeMacroStat MacroDef::InvokeMacro
(const ArgSet & args,
TextStream & outText,
const SourceInfo &si) const
{
if (! _name.GetLength())
{
return kInvokeNotInited;
}
if (args.GetNumArgs() != _numArgs)
{
return kInvokeWrongArgCount;
}
TextStream tmp = _definition;
while (tmp.GetLength())
{
bool stat;
char c;
stat = tmp.Consume (c);
assert (stat);
if ('%' != c)
{
outText.Append (c);
}
else
{
// Looks like a macro argument invocation, maybe!
stat = tmp.Consume (c);
assert (stat); // should have already checked for this in
// AppendMacroExpansion()
if ('%' == c)
{
// Not a macro, just an escaped '%'
outText.Append (c);
}
else
{
int idx = c - '0';
TextStream txt;
stat = tmp.Consume (c);
assert (stat); // should have already checked for
// this in AppendMacroExpansion()
assert (c >= '0');
assert (c <= '9');
idx = idx * 10 + (c - '0');
// AppendMacroExpansion should have already checked for
// proper range
assert (idx > 0);
assert (idx < 100);
txt = args.GetArg(idx-1).GetText(); // index is 0-based
outText.SetCurSourceInfo (si);
outText.Append (txt);
}
}
}
return kInvokeNoError;
}
