Nimgen wrapper for Edlib
Hello! I am trying to make a wrapper for the [edlib](https://github.com/Martinsos/edlib) library. It can be found [here](https://github.com/sstadick/nimedlib). I'm sure I'm missing something simple, but when I try to run the small test in my repo (`nim c -r tests/tnimedlib.nim`), I just get an error message /.nimble/pkgs/nimedlib-0.1.0/nimedlib/edlib.nim(56, 6) Error: implementation of 'nimedlib.edlibFreeAlignResult(result: EdlibAlignResult)[declared in ../../../.nimble/pkgs/nimedlib-0.1.0/nimedlib/edlib.nim(56, 5)]' expected Run To me this would indicate that the function wasn't in the cpp file, but it is, and all the other functions are found just fine it appears. I am not an expert in C land by any means though, so perhaps it's not that simple. Any pointers are appreciated!
Re: Problem trying to compress the http response data!
Try miniz instead. [https://github.com/treeform/miniz](https://github.com/treeform/miniz) zip/zlib.nim defines ulong as 32-bit, so it fails with 64-bit zlibs.
Wrapping C++ class with overloaded constructors
Dear All,
I'm trying to wrap this C++ header:
[https://github.com/cartoonist/kseqpp/blob/master/src/seqio.h](https://forum.nim-lang.org/postActivity.xml#https-github-com-cartoonist-kseqpp-blob-master-src-seqio-h)
which has a constructor SeqStreamIn( const char* filename )
My Nim code is
# Compile with
# nim cpp --cincludes:. --passL:"-lz" kseqpp
import os
const
seqio = "seqio.h"
type
SeqStreamInObj {.header: seqio, importcpp: "klibpp::SeqStreamIn".} =
object
SeqStreamIn = ptr SeqStreamInObj
proc newSeqStreamIn*(fn: cstring): SeqStreamInObj {.importcpp:
"klibpp::SeqStreamIn(#)".}
when isMainModule:
var iss = newSeqStreamIn("sample.fastq".cstring)
Run
However, when I compile, I get an error, error: no matching function for call
to ‘klibpp::SeqStreamIn::SeqStreamIn()’.
Any ideas of what I'm doing wrong?
Re: output order
Evaluation order is left-to-right as written in the manual. Of course, this evaluation order refers to _after_ template/macro expansions.
Re: Trouble when converting c code to nim
It would be helpful to others to indicate your exact problem, like why does it not compile and why you can not solve this? Your above snippet has problems with converting types, because you are trying to mix Nim integers and C unsigned chars. Fixing this is not too hard: proc utf8str_codepoint_len*(s: cstring, utf8len: cint): cint = var codepointLen: cint = 0 let m4 = 128 + 64 + 32 + 16 let m3 = 128 + 64 + 32 let m2 = 128 + 64 var i: cint = 0 while i < utf8len: var c = s[i].int if (c and m4) == m4: inc(i, 3) elif (c and m3) == m3: inc(i, 2) elif (c and m2) == m2: inc(i, 1) inc(i) inc(codepointLen) return codepointLen Run As an alternative you might look into the nim unicode module which offers the runelen() proc which does almost exactly what your above code does.
Re: Trouble when converting c code to nim
Your code is mostly fine, the reason it's only compiling, is due to Nim having a much stricter type system. For other visitors this is the error message is: in.nim(3, 34) Error: type mismatch: got but expected 'cuchar = Char' Run You're probably better off not using the types prefixed by C, those are mostly meant for compability. This is how I would translate your function into more idiomatic Nim: proc utf8str_codepoint_len*(s: string, utf8len: int): int = const m4 = 128'u8 + 64 + 32 + 16 m3 = 128'u8 + 64 + 32 m2 = 128'u8 + 64 var i = 0 while i < utf8len: # in Nim char and uint8/byte are separate types, with the former being only used to represent 8 bit # characters and thus arithmetic functions aren't defined for neither it nor cchar. var c = uint8(s[i]) if (c and m4) == m4: i += 3 elif (c and m3) == m3: i += 2 elif (c and m2) == m2: i += 1 inc result # result is the implicit return value that is like all unassigned variables in Nim set to 0 in the beginning Run
Re: Modern way to pass a sequence to a c function as a void pointer and to cast it back as seq
Well, C _can_ understand it. But that does not mean you should _want_ it to :)
{.emit: """
typedef long long int nim_int;
struct nim_seq_hdr {
nim_int len;
nim_int reserved;
};
struct nim_string {
struct nim_seq_hdr seq;
char *data[0];
};
struct nim_string_seq {
struct nim_seq_hdr seq;
struct nim_string *data[0];
};
void foo(void *ptr)
{
struct nim_string_seq *n = *(struct nim_string_seq **)ptr;
nim_int i;
for(i=0; iseq.len; i++) {
struct nim_string *s = *(struct nim_string **)(>data[i]);
printf("%d -> %d: %s\n", i, s->seq.len, s->data);
}
}
"""}
proc foo(a1: pointer) {.cdecl, importc.}
var a = @["one", "two", "three"]
foo(addr a)
Run
Trouble when converting c code to nim
Hello i have the following piece of code that i want to transform in nim:
int utf8str_codepoint_len( char const* s, int utf8len ) {
int codepointLen = 0;
unsigned char m4 = 128 + 64 + 32 + 16;
unsigned char m3 = 128 + 64 + 32;
unsigned char m2 = 128 + 64;
for ( int i = 0; i < utf8len; ++ i, ++ codepointLen ) {
char c = s[i];
if ( ( c & m4 ) == m4 ) {
i += 3;
} else if ( ( c & m3 ) == m3 ) {
i += 2;
} else if ( ( c & m2 ) == m2 ) {
i += 1;
}
}
return ( codepointLen );
}
Run
I have this for the moment but it's doesn't compile:
proc utf8str_codepoint_len*(s: cstring; utf8len: cint): cint =
var codepointLen: cint = 0
var m4: cuchar = 128 + 64 + 32 + 16
var m3: cuchar = 128 + 64 + 32
var m2: cuchar = 128 + 64
var i: cint = 0
while i < utf8len:
var c: char = s[i]
if (c and m4) == m4:
inc(i, 3)
elif (c and m3) == m3:
inc(i, 2)
elif (c and m2) == m2:
inc(i, 1)
inc(i)
inc(codepointLen)
return codepointLen
Run
Should i keep it in c and import it nim ?
Problem trying to compress the http response data!
I am trying to compress the responses that are sent by http:
import asynchttpserver, asyncdispatch
import zip/zlib
proc handle(req: Request) {.async.} =
if req.headers.hasKey("Accept-Encoding") and
req.headers["Accept-Encoding"] == "gzip":
let headers = newHttpHeaders([("Content-Encoding", "gzip")])
await req.respond(Http200, compress("Yes, it was compressed!"), headers)
else:
await req.respond(Http200, "Compress me please!...")
var server = newAsyncHttpServer()
waitFor server.serve(Port(8080), handle)
Run
But I get the following error message when trying to run this code!
Exception message: zlib version mismatch!
Exception type: [ZlibStreamError]
Error: execution of an external program failed: '/home/hdias/dev/server '
What's is wrong? and how can I get it to work? (my zlib version:
zlib-1:1.2.11-3)
Re: How to create and pass a char*[] to a C function with FFI
The header was like this: int argc, char* argv[] and it only worked with ptr cstringArray.
Re: new experimental nim plugin for neovim
> Any recommendations for other plugins that are useful? Look at plugins by [tpope](https://github.com/tpope/), lots of (must-have) goodies there. Other stuff you'll pick along the way based on your preferences, but here are some of mine: fzf.vim, vim-gitgutter, rainbow, supertab, vim-highlightedyank, vim-bbye
Re: How to create and pass a char*[] to a C function with FFI
ptr cstringArray works.
Re: How to create and pass a char*[] to a C function with FFI
It works, you can pass `ptr Foo` or even `pointer` to any char *. In your case you should probably use `pointer` or `ptr pointer` or `ptr UncheckArray[pointer]`. But without the relevant part of the header, I can't say much more. Anyway the proper way to interface `char *` is `pointer`, you can look into the `alloc` and `alloc0` procs and other low-level proc in `system.nim` as reference.
Re: new experimental nim plugin for neovim
Haven't used neovim before but I just installed it and it's nice. Any recommendations for other plugins that are useful?
Re: How to create and pass a char*[] to a C function with FFI
That's about seq[int] and that technique doesn't work.
Re: How to create and pass a char*[] to a C function with FFI
I believe this is related: [https://forum.nim-lang.org/t/4837#30308](https://forum.nim-lang.org/t/4837#30308)
Re: Modern way to pass a sequence to a c function as a void pointer and to cast it back as seq
I don't think that C will understand Nim's seq. Maybe you want to create a char*[] like me: [https://forum.nim-lang.org/t/4851](https://forum.nim-lang.org/t/4851)
How to create and pass a char*[] to a C function with FFI
cstringArray and ptr UncheckedArray[ptr cstring] don't work. They do work with char** but that's not what I need.
Re: Unexpected error from the C compiler with Option
I am also facing this type of issue and get useful ideas from [https://errorcode0x.com/fixed-asus-error-code-55](https://errorcode0x.com/fixed-asus-error-code-55)/ page. I get some proper solution here. Keep sharing.
Re: Modern way to pass a sequence to a c function as a void pointer and to cast it back as seq
` cFunction(sq[0].unsafeAddr.pointer) ` Run
Modern way to pass a sequence to a c function as a void pointer and to cast it back as seq
Hello I'm looking for help for the following snippet let sq = @["hello", "nim"] proc cFunction(a1: pointer) = # How to cast the pointer to seq[string] proc main() = # How to call cFunction and send sq as a c void pointer Run I have most of the time type mismatch when using cFunction(cast[pointer](sq[0].addr)) cFunction(sq.unsafeAddr) cFunction(sq[0].unsafeAddr) Run
Re: How to set toolchains for cross compilation?
So I finally managed to make it work. test.nim: echo "Hello World!" Run test.nim.cfg: gcc.path = r"C:\COMPILERS\x86_64-w64-mingw32-native\bin" gcc.exe= "x86_64-w64-mingw32-gcc.exe" gcc.cpp.exe= "x86_64-w64-mingw32-g++.exe" gcc.linkerexe = "x86_64-w64-mingw32-gcc.exe" i386.windows.gcc.path = r"C:\COMPILERS\i686-w64-mingw32-native\bin" i386.windows.gcc.exe= "i686-w64-mingw32-gcc.exe" i386.windows.gcc.cpp.exe= "i686-w64-mingw32-g++.exe" i386.windows.gcc.linkerexe = "i686-w64-mingw32-gcc.exe" i386.linux.gcc.path = r"C:\COMPILERS\i686-linux-musl-cross\bin" i386.linux.gcc.exe= "i686-linux-musl-gcc.exe" i386.linux.gcc.cpp.exe= "i686-linux-musl-g++.exe" i386.linux.gcc.linkerexe = "i686-linux-musl-gcc.exe" amd64.linux.gcc.path = r"C:\COMPILERS\x86_64-linux-musl-cross\bin" amd64.linux.gcc.exe= "x86_64-linux-musl-gcc.exe" amd64.linux.gcc.cpp.exe= "x86_64-linux-musl-g++.exe" amd64.linux.gcc.linkerexe = "x86_64-linux-musl-gcc.exe" Run test.bat: nim c -d:release -o:test_win64.exe --os:windows --cpu:amd64 test.nim nim c -d:release -o:test_win32.exe --os:windows --cpu:i386 test.nim nim c -d:release -o:test_lin64.elf --os:linux --cpu:amd64 test.nim nim c -d:release -o:test_lin32.elf --os:linux --cpu:i386 test.nim Run It seems adding ' _.linkerexe ' and '_.path' and using 'gcc.*' for native target fixed everything.
Re: output order
why would it? arguments need to be evaluated first
