1. 12 Jan, 2017 1 commit
  2. 23 Dec, 2016 1 commit
    • Artyom Kazak's avatar
      base: Override Foldable.{toList,length} for NonEmpty · 94d2cce6
      Artyom Kazak authored
      Previously the Foldable instance for NonEmpty used default
      implementations for toList and length.
      
      I assume that the existing implementations
      (i.e. Data.List.NonEmpty.{toList,length}) are better than
      the default ones, and frankly can't see a good reason why they
      might be worse – but if they are, instead of this commit
      we'd have to switch Data.List.NonEmpty.{toList,length}
      to use Foldable.
      
      Reviewers: austin, hvr, bgamari
      
      Reviewed By: bgamari
      
      Subscribers: int-index, thomie
      
      Differential Revision: https://phabricator.haskell.org/D2882
      94d2cce6
  3. 29 Nov, 2016 1 commit
  4. 06 Jun, 2016 1 commit
    • seraphime's avatar
      Add @since annotations to base instances · a90085bd
      seraphime authored
      Add @since annotations to instances in `base`.
      
      Test Plan:
       * ./validate  # some commets shouldn't break the build
       * review the annotations for absurdities.
      
      Reviewers: ekmett, goldfire, RyanGlScott, austin, hvr, bgamari
      
      Reviewed By: RyanGlScott, hvr, bgamari
      
      Subscribers: thomie
      
      Differential Revision: https://phabricator.haskell.org/D2277
      
      GHC Trac Issues: #11767
      a90085bd
  5. 23 Dec, 2015 1 commit
    • Eric Seidel's avatar
      Allow CallStacks to be frozen · 380b25ea
      Eric Seidel authored
      This introduces "freezing," an operation which prevents further
      locations from being appended to a CallStack.  Library authors may want
      to prevent CallStacks from exposing implementation details, as a matter
      of hygiene. For example, in
      
      ```
      head [] = error "head: empty list"
      
      ghci> head []
      *** Exception: head: empty list
      CallStack (from implicit params):
        error, called at ...
      ```
      
      including the call-site of `error` in `head` is not strictly necessary
      as the error message already specifies clearly where the error came
      from.
      
      So we add a function `freezeCallStack` that wraps an existing CallStack,
      preventing further call-sites from being pushed onto it. In other words,
      
      ```
      pushCallStack callSite (freezeCallStack callStack) = freezeCallStack callStack
      ```
      
      Now we can define `head` to not produce a CallStack at all
      
      ```
      head [] =
        let ?callStack = freezeCallStack emptyCallStack
        in error "head: empty list"
      
      ghci> head []
      *** Exception: head: empty list
      CallStack (from implicit params):
        error, called at ...
      ```
      
      ---
      
      1. We add the `freezeCallStack` and `emptyCallStack` and update the
         definition of `CallStack` to support this functionality.
      
      2. We add `errorWithoutStackTrace`, a variant of `error` that does not
         produce a stack trace, using this feature. I think this is a sensible
         wrapper function to provide in case users want it.
      
      3. We replace uses of `error` in base with `errorWithoutStackTrace`. The
         rationale is that base does not export any functions that use CallStacks
         (except for `error` and `undefined`) so there's no way for the stack
         traces (from Implicit CallStacks) to include user-defined functions.
         They'll only contain the call to `error` itself. As base already has a
         good habit of providing useful error messages that name the triggering
         function, the stack trace really just adds noise to the error. (I don't
         have a strong opinion on whether we should include this third commit,
         but the change was very mechanical so I thought I'd include it anyway in
         case there's interest)
      
      4. Updates tests in `array` and `stm` submodules
      
      Test Plan: ./validate, new test is T11049
      
      Reviewers: simonpj, nomeata, goldfire, austin, hvr, bgamari
      
      Reviewed By: simonpj
      
      Subscribers: thomie
      
      Projects: #ghc
      
      Differential Revision: https://phabricator.haskell.org/D1628
      
      GHC Trac Issues: #11049
      380b25ea
  6. 15 Dec, 2015 1 commit
  7. 02 Nov, 2015 1 commit
  8. 31 Oct, 2015 1 commit
  9. 12 Oct, 2015 1 commit
    • Herbert Valerio Riedel's avatar
      base: MRP-refactoring of AMP instances · e737a512
      Herbert Valerio Riedel authored
      This refactors `(>>)`/`(*>)`/`return`/`pure` methods into normal form.
      
      The redundant explicit `return` method definitions are dropped
      altogether.
      
      The explicit `(>>) = (*>)` definitions can't be removed yet, as
      the default implementation of `(>>)` is still in terms of `(*>)`
      (even though that should have been changed according to the AMP but
      wasn't -- see note in GHC.Base for details why this had to be postponed)
      
      A nofib comparision shows this refactoring to result in minor runtime
      improvements (unless those are within normal measurement fluctuations):
      
              Program           Size    Allocs   Runtime   Elapsed  TotalMem
        -------------------------------------------------------------------------
                  Min          -0.0%     -0.0%     -1.6%     -3.9%     -1.1%
                  Max          -0.0%     +0.0%     +0.5%     +0.5%      0.0%
        Geometric Mean         -0.0%     -0.0%     -0.4%     -0.5%     -0.0%
      
      Full `nofib` report at https://phabricator.haskell.org/P68
      
      Reviewers: quchen, alanz, austin, #core_libraries_committee, bgamari
      
      Reviewed By: bgamari
      
      Differential Revision: https://phabricator.haskell.org/D1316
      e737a512
  10. 02 Oct, 2015 1 commit