问题描述
prepare = lib.hm.dag.entryAfter ["writeBoundary"] '' very long script with ${...} '';
我可以用 builtins.readFile
读取它,但它不能代替 ${...}
nix 占位符。
解决方法
您可以使用 substitute
系列的 bash 函数(请参阅 Nixpkgs manual)或使用 substituteAll
Nix 函数来生成执行替换的派生。
substituteAll { src = ./sample.sh; inherit bash; hi = hello; }
sample.sh
:
#!@bash@/bin/bash
@hi@
结果:
$ nix repl <nixpkgs>
nix-repl> substituteAll { src = ./sample.sh; inherit bash; hi = hello; }
«derivation /nix/store/7klv763a0ipgvwf3j84aazkzx2d5rljz-sample.sh.drv»
nix-repl> :b substituteAll { src = ./sample.sh; inherit bash; hi = hello; }
this derivation produced the following outputs:
out -> /nix/store/v03hpzw9ykrbyqpmalnijnyibq3waqhw-sample.sh
nix-repl>
/nix/store/v03hpzw9ykrbyqpmalnijnyibq3waqhw-sample.sh
:
#!/nix/store/a4yw1svqqk4d8lhwinn9xp847zz9gfma-bash-4.4-p23/bin/bash
/nix/store/jmmw0d3nmklwafcwylvrjb9v69wrbcxf-hello-2.10