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diff --git a/doc/manual/src/expressions/generic-builder.md b/doc/manual/src/expressions/generic-builder.md deleted file mode 100644 index cf26b5f82..000000000 --- a/doc/manual/src/expressions/generic-builder.md +++ /dev/null @@ -1,66 +0,0 @@ -# Generic Builder Syntax - -Recall that the [build script for GNU Hello](build-script.md) looked -something like this: - -```bash -PATH=$perl/bin:$PATH -tar xvfz $src -cd hello-* -./configure --prefix=$out -make -make install -``` - -The builders for almost all Unix packages look like this — set up some -environment variables, unpack the sources, configure, build, and -install. For this reason the standard environment provides some Bash -functions that automate the build process. Here is what a builder using -the generic build facilities looks like: - -```bash -buildInputs="$perl" ① - -source $stdenv/setup ② - -genericBuild ③ -``` - -Here is what each line means: - -1. The `buildInputs` variable tells `setup` to use the indicated - packages as “inputs”. This means that if a package provides a `bin` - subdirectory, it's added to `PATH`; if it has a `include` - subdirectory, it's added to GCC's header search path; and so on. - (This is implemented in a modular way: `setup` tries to source the - file `pkg/nix-support/setup-hook` of all dependencies. These “setup - hooks” can then set up whatever environment variables they want; for - instance, the setup hook for Perl sets the `PERL5LIB` environment - variable to contain the `lib/site_perl` directories of all inputs.) - -2. The function `genericBuild` is defined in the file `$stdenv/setup`. - -3. The final step calls the shell function `genericBuild`, which - performs the steps that were done explicitly in the previous build - script. The generic builder is smart enough to figure out whether - to unpack the sources using `gzip`, `bzip2`, etc. It can be - customised in many ways; see the Nixpkgs manual for details. - -Discerning readers will note that the `buildInputs` could just as well -have been set in the Nix expression, like this: - -```nix - buildInputs = [ perl ]; -``` - -The `perl` attribute can then be removed, and the builder becomes even -shorter: - -```bash -source $stdenv/setup -genericBuild -``` - -In fact, `mkDerivation` provides a default builder that looks exactly -like that, so it is actually possible to omit the builder for Hello -entirely. |