haskell-names: Name resolution library for Haskell

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This package takes modules parsed with haskell-src-exts, resolves used names and annotates the parsed module with scoping information.

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Versions0.1, 0.1.1, 0.1.2, 0.2, 0.2.1, 0.3, 0.3.1, 0.3.2,,,,,,,,, 0.3.3,,, 0.4, 0.4.1, 0.5.0, 0.5.1, 0.5.2, 0.5.3, 0.6.0, 0.7.0, 0.8.0, 0.9.0, 0.9.0, 0.9.1, 0.9.2, 0.9.3, 0.9.4, 0.9.5, 0.9.6, 0.9.7
Change logCHANGELOG.md
Dependenciesaeson (>= && <1.3), base (==4.*), bytestring (>= && <0.11), containers (>=0.2 && <0.6), data-lens-light (>= && <0.2), filepath (>=1.1 && <1.5), haskell-src-exts (>=1.18 && <1.20), mtl (>=2.2.1 && <2.3), tagged (>=0.8.4 && <0.9), transformers (>= && <0.6), traverse-with-class (>= && <1.1), uniplate (>=1.5.1 && <1.7) [details]
AuthorPhilipp Schuster, Roman Cheplyaka, Lennart Augustsson
MaintainerPhilipp Schuster
Home pagehttp://documentup.com/haskell-suite/haskell-names
Source repositoryhead: git clone git://github.com/haskell-suite/haskell-names.git
UploadedSat Sep 16 17:31:48 UTC 2017 by PhilippSchuster




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Readme for haskell-names-0.9.0

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haskell-names Build Status

haskell-names does name and module resolution for haskell-src-exts AST.

Namely, it can do the following:


If you're building a development version, then you might also need to install a development version of haskell-src-exts.


An environment is a map from module name to list of symbols the module exports. Symbols are for example types, classes, functions etc. We persist these lists in a JSON format. For example, here are a couple of entries from Prelude.names:

    "name": "map",
    "entity": "value",
    "module": "GHC.Base"
    "name": "IO",
    "entity": "newtype",
    "module": "GHC.Types"

As you see, each entity is annotated with the module where it was originally defined. Additionally, class methods, field selectors, and data constructors are annotated with the class or type they belong to.

haskell-names provides functions readSymbols and writeSymbols to read and write interface files.

Name resolution

The annotate function annotates the given module with scoping information.

Its essence is described in the article Open your name resolution.


The example in examples/HeadUsage.hs shows how you would find out if a Haskell modules given on stdin uses Prelude.head.

% cabal exec -- runghc examples/HeadUsages.hs
one = head [1]
Prelude.head is used at stdin: (1:7) - (1:11)

% cabal exec -- runghc examples/HeadUsages.hs
import Prelude hiding (head)
import Data.Text

f = head (pack "foo")
Congratulations! Your code doesn't use Prelude.head

The example in examples/ModuleExports.hs shows how the resolve function behaves. It expects to find examples/moduleexports.Example.hs and examples/moduleexports/Example/Internal.hs.

% cabal exec -- runghc examples/ModuleExports.hs
Only example: fromList [(ModuleName () "Example",[])]
Only internal: fromList [(ModuleName () "Example.Internal",[Value {symbolModule = ModuleName () "Example.Internal", symbolName = Ident () "details"}])]
Example & Internal: fromList [(ModuleName () "Example",[Value {symbolModule = ModuleName () "Example.Internal", symbolName = Ident () "details"}]),(ModuleName () "Example.Internal",[Value {symbolModule = ModuleName () "Example.Internal", symbolName = Ident () "details"}])]
Internal & Example: fromList [(ModuleName () "Example",[Value {symbolModule = ModuleName () "Example.Internal", symbolName = Ident () "details"}]),(ModuleName () "Example.Internal",[Value {symbolModule = ModuleName () "Example.Internal", symbolName = Ident () "details"}])]
Example after Internal: fromList [(ModuleName () "Example",[Value {symbolModule = ModuleName () "Example.Internal", symbolName = Ident () "details"}]),(ModuleName () "Example.Internal",[Value {symbolModule = ModuleName () "Example.Internal", symbolName = Ident () "details"}])]
Internal after Example: fromList [(ModuleName () "Example",[]),(ModuleName () "Example.Internal",[Value {symbolModule = ModuleName () "Example.Internal", symbolName = Ident () "details"}])]

API documentation

The core module you need is Language.Haskell.Names

Other modules are more experimental, less documented, and you probably don't need them anyway.

Known issues

See the list of all issues.


Philipp Schuster is the primary maintainer.

Adam Bergmark is the backup maintainer. Please get in touch with him if the primary maintainer cannot be reached.