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Diffstat (limited to 'dev-haskell/fclabels/metadata.xml')
| -rw-r--r-- | dev-haskell/fclabels/metadata.xml | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/dev-haskell/fclabels/metadata.xml b/dev-haskell/fclabels/metadata.xml new file mode 100644 index 00000000000..1ad04331260 --- /dev/null +++ b/dev-haskell/fclabels/metadata.xml @@ -0,0 +1,26 @@ +<?xml version="1.0" encoding="UTF-8"?> +<!DOCTYPE pkgmetadata SYSTEM "http://www.gentoo.org/dtd/metadata.dtd"> +<pkgmetadata> + <herd>haskell</herd> + <longdescription> + This package provides first class labels that can act as + bidirectional record fields. The labels can be derived + automatically using Template Haskell which means you don't have + to write any boilerplate yourself. The labels are implemented as + lenses and are fully composable. Labels can be used to /get/, + /set/ and /modify/ parts of a datatype in a consistent way. + + See "Data.Label" for an introductory explanation. + + Internally lenses are not tied to Haskell functions directly, + but are implemented as arrows. Arrows allow the lenses to be run + in custom computational contexts. This approach allows us to + make partial lenses that point to fields of multi-constructor + datatypes in an elegant way. + + See the "Data.Label.Maybe" module for the use of partial labels. + + > 1.0.3 -> 1.0.4 + > - Bugfix to compile on GHC 6.12 again. + </longdescription> +</pkgmetadata> |