diff options
Diffstat (limited to 'lib/meta.nix')
-rw-r--r-- | lib/meta.nix | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/lib/meta.nix b/lib/meta.nix new file mode 100644 index 000000000000..a5afce9e0cb1 --- /dev/null +++ b/lib/meta.nix @@ -0,0 +1,48 @@ +/* Some functions for manipulating meta attributes, as well as the + name attribute. */ + +rec { + + + /* Add to or override the meta attributes of the given + derivation. + + Example: + addMetaAttrs {description = "Bla blah";} somePkg + */ + addMetaAttrs = newAttrs: drv: + drv // { meta = (if drv ? meta then drv.meta else {}) // newAttrs; }; + + + /* Change the symbolic name of a package for presentation purposes + (i.e., so that nix-env users can tell them apart). + */ + setName = name: drv: drv // {inherit name;}; + + + /* Like `setName', but takes the previous name as an argument. + + Example: + updateName (oldName: oldName + "-experimental") somePkg + */ + updateName = updater: drv: drv // {name = updater (drv.name);}; + + + /* Append a suffix to the name of a package. !!! the suffix should + really be appended *before* the version, at least most of the + time. + */ + appendToName = suffix: updateName (name: "${name}-${suffix}"); + + + /* Decrease the nix-env priority of the package, i.e., other + versions/variants of the package will be preferred. + */ + lowPrio = drv: addMetaAttrs { priority = "10"; } drv; + + /* Increase the nix-env priority of the package, i.e., this + version/variant of the package will be preferred. + */ + hiPrio = drv: addMetaAttrs { priority = "-10"; } drv; + +} |