How are scopes chained in nullc ? #30
Description
I'm trying to add a compiler warning for shadowed variables but I'm having trouble understand scopes in nullc, I started by copying and changing Report(ExpressionContext &ctx, SynBase *source, const char *msg, ...) then changed bool CheckVariableConflict(ExpressionContext &ctx, SynBase *source, InplaceStr name) to issue the warning then I'm getting this warnings when running nullc:
WARNING: name 'x' is already taken for a variable in outer scope
WARNING: name 'y' is already taken for a variable in outer scope
WARNING: name 'x' is already taken for a variable in outer scope
WARNING: name 'y' is already taken for a variable in outer scope
WARNING: name 'z' is already taken for a variable in outer scope
WARNING: name 'x' is already taken for a variable in outer scope
WARNING: name 'y' is already taken for a variable in outer scope
WARNING: name 'z' is already taken for a variable in outer scope
WARNING: name 'w' is already taken for a variable in outer scope
WARNING: name 'node' is already taken for a variable in outer scope
WARNING: name 'node' is already taken for a variable in outer scope
WARNING: name 'node' is already taken for a variable in outer scope
WARNING: name 'node' is already taken for a variable in outer scope
WARNING: name 'node' is already taken for a variable in outer scope
WARNING: name 'node' is already taken for a variable in outer scope
I understand that I need to search for the symbol name in outer scopes to decide to show the warning.
How are scopes chained in nullc ?
NULLC_PRINT_FORMAT_CHECK(3, 4) void Warning(ExpressionContext &ctx, SynBase *source, const char *msg, ...)
{
va_list args;
va_start(args, msg);
vprintf(msg, args);
//ReportAt(ctx, source, source->pos.begin, msg, args);
va_end(args);
}
bool CheckVariableConflict(ExpressionContext &ctx, SynBase *source, InplaceStr name)
{
if(LookupTypeByName(ctx, name.hash()))
{
Report(ctx, source, "ERROR: name '%.*s' is already taken for a type", FMT_ISTR(name));
return true;
}
if(IdentifierLookupResult *lookup = LookupObjectByName(ctx, name.hash()))
{
if(lookup->variable)
{
if(lookup->variable->scope == ctx.scope) {
Report(ctx, source, "ERROR: name '%.*s' is already taken for a variable in current scope", FMT_ISTR(name));
return true;
}
else {
Warning(ctx, source, "WARNING: name '%.*s' is already taken for a variable in outer scope\n", FMT_ISTR(name));
}
}
if(lookup->function && lookup->function->scope == ctx.scope)
{
Report(ctx, source, "ERROR: name '%.*s' is already taken for a function", FMT_ISTR(name));
}
}
if(FindNamespaceInCurrentScope(ctx, name))
{
Report(ctx, source, "ERROR: name '%.*s' is already taken for a namespace", FMT_ISTR(name));
return true;
}
return false;
}