Update README.md

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Lennart Spitzner 2016-09-29 21:41:11 +02:00 committed by GitHub
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@ -13,7 +13,8 @@ The main differences are:
* Exposes an evil monadic interface, which allows for much nicer binding of
command part results to some variable name, where in `optparse-applicative`
you easily lose track of what field you are modifying after the 5th `<*>`.
you easily lose track of what field you are modifying after the 5th `<*>`
(admittedly, i think -XRecordWildCards improves on that issue already.)
Evil, because you are not allowed to use the monad's full power in this
case, i.e. there is a constraint that is not statically enforced.
@ -62,7 +63,7 @@ That means that checking if a combination of flags is allowed must be done
after parsing. (But different commands and their subcommands have separate
sets of flags.)
## Package intentions
## (abstract) Package intentions
Consider a commandline invocation like "ghc -O -i src -Main.hs -o Main". This
package provides a way for the programmer to simultaneously define the
@ -73,10 +74,12 @@ for the user. More specifically, i had three goals in mind:
2. Extract understandable usage/help commandline documents/texts from that
descriptions, think of `ghc --help` or `stack init --help`.
3. Extract necessary information to compute commandline completion results
from any partial input.
from any partial input. (This is not implemented to any serious degree.)
## Semantics
(Sorry, this description is severely lacking, I know.)
Basic elements of a command are flags, parameters and subcommands. These can
be composed in certain ways, i.e. flags can have a (or possibly multiple?)
parameters; parameters can be grouped into sequences, and commands can have