Add support for parsing digraphs#158
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Thanks for the contribution! Looking at https://en.cppreference.com/cpp/language/operator_alternative, they have this example which your PR fails to parse:
%:include <iostream>
struct X
<%
compl X() <%%> // destructor
X() <%%>
X(const X bitand) = delete; // copy constructor
// X(X and) = delete; // move constructor
bool operator not_eq(const X bitand other)
<%
return this not_eq bitand other;
%>
%>;
int main(int argc, char* argv<::>)
<%
// lambda with reference-capture:
auto greet = <:bitand:>(const char* name)
<%
std::cout << "Hello " << name
<< " from " << argv<:0:> << '\n';
%>;
if (argc > 1 and argv<:1:> not_eq nullptr)
greet(argv<:1:>);
else
greet("Anon");
%>I think it's fine to not support the weird include thing or named versions of operators like bitand, but if you replace those it still gets stuck on the char* argv<::>.
I asked GPT to solve the digraph problem, I think it's approach is slightly better and parses these cases (see #160)
| """<% %> should work as { } in a function body context (body is skipped).""" | ||
| # The parser skips function bodies but must recognise the braces. | ||
| content = """\ | ||
| #include <iostream> |
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For any future contributions, please use python -m cxxheaderparser.gentest to generate tests.
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C++ allows for digraphs as a replacement for certain tokens. While trigraphs were removed digraphs are still valid in modern C++. Namely, the following replacements can be used because some computer keyboards don't have all these characters or something:
<:replaces[:>replaces]<%replaces{%>replaces}So this means that something like
Is valid C++ code ( verified as compiling on https://godbolt.org/ but giving a parse error on https://robotpy.github.io/cxxheaderparser/ )
This change to support parsing for these tokens will allow cxxheaderparser to parse legacy C or C++ code that uses these weird symbols.