BASIC in C++

vezzy-fnord wrote: post #3

Wasn't the original Bourne shell also written with (more basic) C preprocessor macros to imitate original ALGOL-style constructs?

Yes. It was the inspiration for the IOCCC (International Obfuscated C Code Competition).

http://www.ioccc.org/faq.html

But the macros were the least of its problems: It allocated memory by trapping SIGSEGV (SIGnal for SEGmentiation Violation; that is, the signal the OS sends a program when it's tried to access memory beyond the region it owns); the function which caught SIGSEGV allocated more RAM. This made it difficult to port sh to the Motorola 68000-based computers which were the first generation of Unix workstations.

http://www.in-ulm.de/~mascheck/bourne/segv.html

https://news.ycombinator.com/item?id=8843951

Re: BASIC in C++

#7

Post by Rangi42 » Sat, Jun 20, 2015, 10:24 PM UTC

If you #define END as "return(0);}" and put "int main(){" at the bottom of basic.hpp, you can have a complete BASIC program with #include "basic.hpp" at the top as the only indication that it's C++.

    #include "basic.hpp"
    _10: LET X = 1;
    // ...
    _150: END

I think multiple data types could also be added in a way that mostly fits with BASIC syntax. GW-BASIC uses sigil suffixes on variable names to denote their type:[1]

    $  String variable
    %  Integer variable
    !  Single-precision variable (default)
    #  Double-precision variable

Something like this might be possible with unions (e.g. _10: LET X.D = 3.14; _20: LET N.I = 42;), or you can tolerate a few different LET macros (LETS, LETI, LETD).

[1] http://www.antonis.de/qbebooks/gwbasman/chapter%206.html

Re: BASIC in C++

#8

Post by thought_alarm » Sat, Jun 20, 2015, 10:57 PM UTC

    ] 10 PRINT "HELLO'

    ] RUN

    ERROR
    In file included from dummy.cpp:1:
    In file included from /usr/include/c++/v1/vector:243:
    In file included from /usr/include/c++/v1/__bit_reference:15:
    In file included from /usr/include/c++/v1/algorithm:594:
    /usr/include/c++/v1/memory:1425:36: error: calling a private constructor of class 'std::__1::unique_ptr >'
    ::new ((void*)__p) _Tp(_STD::forward(__args)...);
    ^
    /usr/include/c++/v1/memory:1358:14: note: in instantiation of function template specialization
    'std::__1::allocator_traits > >
    >::__construct >, std::__1::unique_ptr > &>' requested here
    {__construct(__has_construct(),
    ^
    /usr/include/c++/v1/vector:781:25: note: in instantiation of function template specialization
    'std::__1::allocator_traits > >
    >::construct >, std::__1::unique_ptr > &>' requested here
    __alloc_traits::construct(__a, _STD::__to_raw_pointer(this->__end_), *__first);
    ^
    /usr/include/c++/v1/vector:924:9: note: in instantiation of function template specialization
    'std::__1::vector >,
    std::__1::allocator > >
    >::__construct_at_end > *>' requested here
    __construct_at_end(__x.__begin_, __x.__end_);
    ^
    dummy.cpp:7:37: note: in instantiation of member function 'std::__1::vector >, std::__1::allocator > >
    >::vector' requested here
    std::vector> bar = foo;
    ^
    /usr/include/c++/v1/memory:1997:5: note: declared private here
    unique_ptr(const unique_ptr&);
    ^
    1 error generated.

Re: BASIC in C++

#9

Post by WalterBright » Sat, Jun 20, 2015, 11:26 PM UTC

blackhole wrote: post #2

I can't decide if this is brilliant or terrifying.

This is why D doesn't have AST macros, a preprocessor, and makes operator overloading difficult for any purpose other than arithmetic.

Programmers can (and do) still create DSLs in D by using string mixins and CTFE.

Re: BASIC in C++

#10

Post by orionblastar » Sat, Jun 20, 2015, 11:31 PM UTC

I'm still liking Visual BASIC 6.0 before the Dotnet era.

A shame that newer versions of Windows have problems installing it.

There is Jabaco that takes VB 6.0 syntax and compiles it to Java bytecode: http://www.jabaco.org/

It doesn't have ADO database support so I can't write apps with Databases in VB 6.0 and port them to Jabaco.

This trying to make C++ do BASIC commands is hard, might as well use this instead: http://robhagemans.github.io/pcbasic/

You can find the Classic BASIC games here: http://www.vintage-basic.net/games.html

They should work with PC-BASIC.