Return a gexp that surrounds BODY with a definition of the legacy '%build-inputs', '%outputs', and '%output' variables based on INPUTS, a list of name/gexp-input tuples, and OUTPUTS, a list of strings.

Return as a value in %STORE-MONAD the derivation or store item corresponding to OBJ for SYSTEM, cross-compiling for TARGET if TARGET is true. OBJ must be an object that has an associated gexp compiler, such as a <package>.

Return a directory that is the union of THINGS, where THINGS is a list of file-like objects denoting directories. For example:

(directory-union "guile+emacs" (list guile emacs))

yields a directory that is the union of the 'guile' and 'emacs' packages.

Call RESOLVE-COLLISION when several files collide, passing it the list of colliding files. RESOLVE-COLLISION must return the chosen file or #f, in which case the colliding entry is skipped altogether.

When COPY? is true, copy files instead of creating symlinks. When QUIET? is true, the derivation will not print anything.

Return a <computed-file> that builds a directory containing all of FILES. Each item in FILES must be a two-element list where the first element is the file name to use in the new directory, and the second element is a gexp denoting the target file. Here's an example:

(file-union "etc" `(("hosts" ,(plain-file "hosts" "127.0.0.1 localhost")) ("bashrc" ,(plain-file "bashrc" "alias ls='ls --color'")) ("libvirt/qemu.conf" ,(plain-file "qemu.conf" ""))))

This yields an 'etc' directory containing these two files.

Return the list of Guile module names GEXP relies on. If (gexp? GEXP) is false, meaning that GEXP is a plain Scheme object, return the empty list.

Return the S-expression corresponding to GEXP, but do not lower anything. As a result, the S-expression will be approximate if GEXP has references.

Return #t if OBJECT leads to a file in the store once unquoted in a G-expression; otherwise return #f.

Return the list of OpenPGP fingerprints authorized to sign COMMIT, based on authorizations listed in its parent commits. If one of the parent commits does not specify anything, fall back to DEFAULT-AUTHORIZATIONS.