Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

Replace Foldable1 primitives #512

Merged
merged 7 commits into from
Sep 8, 2013
Merged

Replace Foldable1 primitives #512

merged 7 commits into from
Sep 8, 2013

Commits on Sep 3, 2013

  1. The foldMap{Left,Right}1 formulation of Foldable1.

    @S11001001
    S11001001 committed Sep 3, 2013
    Configuration menu
    Copy the full SHA
    f29c54d View commit details
    Browse the repository at this point in the history

Commits on Sep 4, 2013

  1. Foldable#foldMap{Left,Right}1Opt

    @S11001001
    S11001001 committed Sep 4, 2013
    Configuration menu
    Copy the full SHA
    b957f05 View commit details
    Browse the repository at this point in the history

  2. Reimplement core Foldable1 instances in terms of foldMap{Left,Right}1.

    @S11001001
    S11001001 committed Sep 4, 2013
    Configuration menu
    Copy the full SHA
    17c9f21 View commit details
    Browse the repository at this point in the history

  3. Replace the structure tests on fold{Left,Right}1 with foldMap1 consis… 

    …tency checks.

It is now a free theorem that the call structure of a Foldable1's left
fold looks like f(f(f(z(a), a), a), a) for some arbitrary depth,
i.e. is called left-associative.  Likewise, the left fold must be
called as f(a, f(a, f(a, z(a)))) for some arbitrary depth.

We formerly tested this property, but with foldMapLeft1 and
foldMapRight1 as primitives with the above free theorems, this is no
longer necessary.  So we just reformulate the (still valuable)
consistency checks from Foldable.
    @S11001001
    S11001001 committed Sep 4, 2013
    Configuration menu
    Copy the full SHA
    dcc224e View commit details
    Browse the repository at this point in the history

  4. Remove Arbitrary Free.Return; it is unused.

    @S11001001
    S11001001 committed Sep 4, 2013
    Configuration menu
    Copy the full SHA
    40663fb View commit details
    Browse the repository at this point in the history

  5. Override foldMap{Left,Right}1Opt in Foldable1.

    @S11001001
    S11001001 committed Sep 4, 2013
    Configuration menu
    Copy the full SHA
    594fb72 View commit details
    Browse the repository at this point in the history

  6. Syntax for foldMap{Left,Right}1{,Opt}.

    @S11001001
    S11001001 committed Sep 4, 2013
    Configuration menu
    Copy the full SHA
    5cd164e View commit details
    Browse the repository at this point in the history