dump-0.2.7: FEATURES.md

# Description

To attain a changelog of this library between two arbitrary versions
you ask git for a diff on this file. For example:

    git diff v0.2.0..v0.2.6 -- FEATURES.md

Alternatively, you may obtain a diff between two versions via any online
diffing service, [such as this one](http://www.diffnow.com/?url1=https://raw.githubusercontent.com/Wizek/dump/v0.2.0/FEATURES.md&url2=https://raw.githubusercontent.com/Wizek/dump/v0.2.6/FEATURES.md).

# Features

* Use it with Debug.Trace: `trace [d|x, y, z|] x`
* Use it with Test.QuickCheck: `counterexample [d|x, y, z|]`
* Use it inside the IO monad: `putStrLn [d|x, y, z|]`

* print out a variable `let a = 1 in print [d|a|]` outputing: `(a) = 1`
* print out an expression `print [d|1 + 2|]` outputting: `(1 + 2) = 3`
* refer to variables in the expression `let a = [1..3] in print [d|map (+1) a|]`
  outputing: `(map (+1) a) = [2,3,4]`
* print out multiple expressions `[d|1+2, 3+4|]` -> "(1+2) = 3   (3+4) = 7"
* tries a bit to line up expressions in columns.

  ```haskell
  main = do
    f 22
    f 333
    where f a = putStrLn [d|a, a+2|]
  ```
  Outputs:

        (a) = 22          (a+2) = 24
        (a) = 333         (a+2) = 335

# Beta features

* Support for expressions that contain commas inside them:
  An example: `[d|1, [2, 3]|]` -> "(1) = 1   ([2, 3]) = [2,3]"

  If your expression is invalid Haskell, such as `[d| ([)] |]` the generated
  code will be invalid as well, but could be slightly transformed. If you get
  cryptic error messages because of this, please let us know by opening
  an issue on GitHub.

# Known issues

n/a

# Miscellaneous

* Refactored and conceptually clean code
* Some Haddock documentation. Perhaps more to come
* Description in FEATURES.md
* Readme contains examples for print and QuickCheck. Perhaps more to come.