Eelco Dolstra
112ee89501
* A better substitute mechanism. Instead of generating a store expression for each store path for which we have a substitute, we can have a single store expression that builds a generic program that is invoked to build the desired store path, which is passed as an argument. This means that operations like `nix-pull' only produce O(1) files instead of O(N) files in the store when registering N substitutes. (It consumes O(N) database storage, of course, but that's not a performance problem). * Added a test for the substitute mechanism. * `nix-store --substitute' reads the substitutes from standard input, instead of from the command line. This prevents us from running into the kernel's limit on command line length.
*** Nix *** For installation and usage instructions, please read the manual, which can be found in `docs/manual/manual.html', and additionally at the Nix website at <http://www.cs.uu.nl/groups/ST/Trace/Nix>.