Nim language support

[Nuc1eoN]

Nim is a compiled language that is as fast and efficient as C but with a python-like syntax and many other features. It compiles to native C code (just like C++ in the old days) but lately also to javascript.

I would love to see Nim support in xmake and would certainly use it for my Nim projects :)

Nim has its own nimble package/project manager which could be compared to rust's cargo. I am not sure if in xmake we would implement support through nimble or bare nim compiler commands, or maybe both. But I guess the rust implementation could be a guideline.

[waruqi]

I have supported it. #1759

Console

add_rules("mode.debug", "mode.release")

target("test")
    set_kind("binary")
    add_files("src/main.nim")

$ xmake -v
[ 33%]: linking.release test
/usr/local/bin/nim c --opt:speed --nimcache:build/.gens/test/macosx/x86_64/release/nimcache -o:b
uild/macosx/x86_64/release/test src/main.nim
[100%]: build ok!

Static Library

add_rules("mode.debug", "mode.release")

target("foo")
    set_kind("static")
    add_files("src/foo.nim")

target("test")
    set_kind("binary")
    add_deps("foo")
    add_files("src/main.nim")

$ xmake -v
[ 33%]: linking.release libfoo.a
/usr/local/bin/nim c --opt:speed --nimcache:build/.gens/foo/macosx/x86_64/release/nimcache --app
:staticlib --noMain --passC:-DNimMain=NimMain_B6D5BD02 --passC:-DNimMainInner=NimMainInner_B6D5B
D02 --passC:-DNimMainModule=NimMainModule_B6D5BD02 --passC:-DPreMain=PreMain_B6D5BD02 --passC:-D
PreMainInner=PreMainInner_B6D5BD02 -o:build/macosx/x86_64/release/libfoo.a src/foo.nim
[ 66%]: linking.release test
/usr/local/bin/nim c --opt:speed --nimcache:build/.gens/test/macosx/x86_64/release/nimcache --pa
ssL:-Lbuild/macosx/x86_64/release --passL:-lfoo -o:build/macosx/x86_64/release/test src/main.nim
[100%]: build ok!

For static libraries, there is currently a _NimMain symbol redefinition bug that needs to be fixed. At present, I can only fix it temporarily through the workaround solution.

See nim-lang/Nim#15955

My workaround solution

function buildargv(self, sourcefiles, targetkind, targetfile, flags)
    local flags_extra = {}
    if targetkind == "static" then
        -- fix multiple definition of `NimMain', it is only workaround solution
        -- we need to wait for this problem to be resolved
        --
        -- @see https://github.com/nim-lang/Nim/issues/15955
        local uniquekey = hash.uuid(targetfile):split("-", {plain = true})[1]
        table.insert(flags_extra, "--passC:-DNimMain=NimMain_" .. uniquekey)
        table.insert(flags_extra, "--passC:-DNimMainInner=NimMainInner_" .. uniquekey)
        table.insert(flags_extra, "--passC:-DNimMainModule=NimMainModule_" .. uniquekey)
        table.insert(flags_extra, "--passC:-DPreMain=PreMain_" .. uniquekey)
        table.insert(flags_extra, "--passC:-DPreMainInner=PreMainInner_" .. uniquekey)
    end
    return self:program(), table.join("c", flags, flags_extra, "-o:" .. targetfile, sourcefiles)
end

Shared Library

add_rules("mode.debug", "mode.release")

target("foo")
    set_kind("shared")
    add_files("src/foo.nim")

target("test")
    set_kind("binary")
    add_deps("foo")
    add_files("src/main.nim")

$ xmake -rv
[ 33%]: linking.release libfoo.dylib
/usr/local/bin/nim c --opt:speed --nimcache:build/.gens/foo/macosx/x86_64/release/nimcache --app
:lib --noMain -o:build/macosx/x86_64/release/libfoo.dylib src/foo.nim
[ 66%]: linking.release test
/usr/local/bin/nim c --opt:speed --nimcache:build/.gens/test/macosx/x86_64/release/nimcache --pa
ssL:-Lbuild/macosx/x86_64/release --passL:-lfoo -o:build/macosx/x86_64/release/test src/main.nim
[100%]: build ok!

With C Library

add_rules("mode.debug", "mode.release")

target("foo")
    set_kind("static")
    add_files("src/*.c")

target("test")
    set_kind("binary")
    add_deps("foo")
    add_files("src/main.nim")

Use packages

add_rules("mode.debug", "mode.release")

add_requires("zlib")

target("test")
    set_kind("binary")
    add_files("src/main.nim")
    add_packages("zlib")

main.nim

proc zlibVersion(): cstring {.cdecl, importc}

echo zlibVersion()

$ xmake -v
[ 33%]: linking.release test
/usr/local/bin/nim c --opt:speed --nimcache:build/.gens/test/macosx/x86_64/release/nimcache --pas
sL:-L/Users/ruki/.xmake/packages/z/zlib/1.2.11/b76a297309d14c09b42cfe3927260a51/lib --passL:-lz -
o:build/macosx/x86_64/release/test src/main.nim
[100%]: build ok!
$ xmake r
1.2.11

[waruqi]

Some apis for nim

• add_ncflags: for source file flags
• add_ncldflags: for linker
• add_ncarflags: for archive
• add_ncshflags: for dynamic linker

[waruqi]

I will improve the package management to directly install and integrate packages from nimble later, for example:

add_requires("nimble::zlib")

target("test")
    set_kind("binary")
    add_files("src/main.nim")
    add_packages("nimble::zlib")

However, even if there is no nimble yet, we can use xmake's package management to directly integrate the c/c++ package from xmake-repo/vcpkg/conan in the nim project.

add_requires("zlib", "vcpkg::libpng")

target("test")
    set_kind("binary")
    add_files("src/main.nim")
    add_packages("zlib", "vcpkg::libpng")

[waruqi]

More Examples: https://github.com/xmake-io/xmake/tree/dev/tests/projects/nim

Project templates

xmake create -l nim -t console test
xmake create -l nim -t static test
xmake create -l nim -t shared test

[waruqi]

We can use nimble packages now

Nimble packages

https://github.com/xmake-io/xmake/tree/dev/tests/projects/nim/nimble_package

add_rules("mode.debug", "mode.release")

add_requires("nimble::zip >0.3")

target("test")
    set_kind("binary")
    add_files("src/main.nim")
    add_packages("nimble::zip")

main.nim

import zip/zlib

echo zlibVersion()

Native packages

https://github.com/xmake-io/xmake/tree/dev/tests/projects/nim/native_package

add_rules("mode.debug", "mode.release")

add_requires("zlib")

target("test")
    set_kind("binary")
    add_files("src/main.nim")
    add_packages("zlib")

main.nim

proc zlibVersion(): cstring {.cdecl, importc}

echo zlibVersion()