undefined | Better HN

0 pointscoldtea2y ago0 comments

>The very common thing I want to use in C is some sort of variable size string object. But no, I have to dynamically allocate a buffer that I know will be at least the right size for any text I ever put into it, or do I create a buffer that's the correct size for that string but re-alloc if I ever change it to a longer string. But then how do I store the buffer size?

As a C programmer shouldn't you have a library abstracting all this by now? Either your own or one of the dozens available, including pascal-style strings?

0 comments

xigoi2y ago

Okay, so you write your own string library. Now you'd like to do the same thing for resizable arrays, so you write a resizable array li… oops, you can't, because C doesn't have parametric types.

tpoacher2y ago

He didn't say "write your own library". He said "use" one (your own if you prefer). Or are you going to suggest there are no good string handling libraries for C?

xigoi2y ago

It doesn't matter. My point is that it's not possible, not for you and not for anyone else, to implement a type-safe generic resizable array library in C.

flohofwoe2y ago

Preprocessor macros are an entirely valid tool in the C language toolbox, even if demonized by C++ coders.

pjmlp2y ago

Even Macro Assemblers from the MS-DOS and Amiga days are better than C pre-processor macros.

melagonster2y ago

it is black magic, absolutely respect C developers.

1 more reply

flashgordon2y ago

My c knowledge is obviously old. I wonder if the author is lamenting the lack of a "modern" string manipulation in the standard library beyond just working on char buffers?

jacquesm2y ago

It's funny how both C and LISP programmers seem to suffer from NIH to the point that they'll roll their own just for the heck of it rather than to first see if there is a library that they can use.

The long term cost of those decisions as well as the number of really bad bugs (and security issues) that can be traced back to one-off code is likely much larger than the same figure for well used libraries. But it all sort of evens out whenever a bug in such a library is found because then it is so widespread that lots of systems will suffer.

Weird how that works.

coldteaOP2y ago

>It's funny how both C and LISP programmers seem to suffer from NIH to the point that they'll roll their own just for the heck of it rather than to first see if there is a library that they can use.

Well, not sure about the LISP programmers, but C programmers have a good reason: they work under different environments (from embedded to Windows, legacy UNIX, the latest Ubuntu, ...) and also have different needs, regarding allocation, string management, etc. So one-size-fits-all lib might not cut it for everybody. It can also be as simple as having an inherited codebase which uses something else.

Still, there are popular string libraries, and C programmers do use them when they can.

kaba02y ago

What exactly is a problem with C++’s strings, or especially Rust’s? Everything you mentioned can be controlled as explicitly as you want.

The only problem is C is simply not expressive enough to have proper abstractions like that.

4 more replies

j / k navigate · click thread line to collapse

0 comments

xigoi2y ago

Okay, so you write your own string library. Now you'd like to do the same thing for resizable arrays, so you write a resizable array li… oops, you can't, because C doesn't have parametric types.

tpoacher2y ago

He didn't say "write your own library". He said "use" one (your own if you prefer). Or are you going to suggest there are no good string handling libraries for C?

xigoi2y ago

It doesn't matter. My point is that it's not possible, not for you and not for anyone else, to implement a type-safe generic resizable array library in C.

flohofwoe2y ago

Preprocessor macros are an entirely valid tool in the C language toolbox, even if demonized by C++ coders.

pjmlp2y ago

Even Macro Assemblers from the MS-DOS and Amiga days are better than C pre-processor macros.

melagonster2y ago

it is black magic, absolutely respect C developers.

1 more reply

flashgordon2y ago

My c knowledge is obviously old. I wonder if the author is lamenting the lack of a "modern" string manipulation in the standard library beyond just working on char buffers?

jacquesm2y ago

It's funny how both C and LISP programmers seem to suffer from NIH to the point that they'll roll their own just for the heck of it rather than to first see if there is a library that they can use.

Weird how that works.

coldteaOP2y ago

Still, there are popular string libraries, and C programmers do use them when they can.

kaba02y ago

What exactly is a problem with C++’s strings, or especially Rust’s? Everything you mentioned can be controlled as explicitly as you want.

The only problem is C is simply not expressive enough to have proper abstractions like that.

4 more replies

j / k navigate · click thread line to collapse