Documentation

A monad allowing one to emit elements of type a. Semantically equivalent to Writer (DList a) r, but:

1. is faster, being based on the Church-encoded free monad
2. implements Monoid, so that all the Data.Foldable convenience is supported
3. has better ergonomics as it doesn't require the user to wrap a values into DLists

This type is also semantically equivalent to Stream (Of a) Identity r.

Useful for monadically creating tree-like structures, for example the following

import Data.Tree
yield = embed . pure
main = putStrLn . drawTree . Node "a" . toList $ do
    yield "b"
    nestWith (Node "c") $ do
        yield "d"
        yield "e"
    yield "f"

will produce

-a
|
+- b
|
+- c
|  |
|  +- d
|  |
|  `- e
|
`- f

Embed the given value into a Layer-like type (either Layer itself or a monad transformer stack with Layer at the bottom).

Collapse the given Layer into a single element by converting it into a list, applying the given function to the result and embedding it back.

A TestTree of tests under some name prefix.

Run a TestNested computation to produce a TestTree (without actually executing the tests).

Descend into a folder.

Descend into a folder for a TestNested computation.

Like testNestedM but adds a subdirectory corresponding to the GHC version being used.

Run a list of TestNested computation to produce a TestTree (without actually executing the tests).

Descend into a folder for a list of tests.

Descend into a folder for a list of TestNested computations.

Like testNested but adds a subdirectory corresponding to the GHC version being used.

Check the contents of a file against a Text.

Check the contents of a file against a Text.

Check the contents of a file against a Doc.

Check the contents of a file against a Doc.

Check the contents of a file under a name prefix against a Text.

Check the contents of a file under a name prefix against a Text.

Check the contents of a file under a name prefix against a Text.

Check the contents of a file under a name prefix against a Text.

Given a lists of FilePaths and a filename, concatenate the members of the list together, append the GHC version number, then append the filename. We use this to create GHC-version-dependent golden files.