*haskellmode.txt* Haskell Mode Plugins 05/07/2008
Authors:
Claus Reinke <claus.reinke@talk21.com> ~
Homepage:
http://www.cs.kent.ac.uk/people/staff/cr3/toolbox/haskell/Vim/
CONTENTS *haskellmode*
1. Overview |haskellmode-overview|
1.1 Runtime Requirements |haskellmode-requirements|
1.2 Quick Reference |haskellmode-quickref|
2. Settings |haskellmode-settings|
2.1 GHC and web browser |haskellmode-settings-main|
2.2 Fine tuning - more configuration options |haskellmode-settings-fine|
3. GHC Compiler Integration |haskellmode-compiler|
4. Haddock Integration |haskellmode-haddock|
4.1 Indexing |haskellmode-indexing|
4.2 Lookup |haskellmode-lookup|
4.3 Editing |haskellmode-editing|
5. Hpaste Integration |haskellmode-hpaste|
6. Additional Resources |haskellmode-resources|
==============================================================================
*haskellmode-overview*
1. Overview ~
The Haskell mode plugins provide advanced support for Haskell development
using GHC/GHCi on Windows and Unix-like systems. The functionality is
based on Haddock-generated library indices, on GHCi's interactive
commands, or on simply activating (some of) Vim's built-in program editing
support in Haskell-relevant fashion. These plugins live side-by-side with
the pre-defined |syntax-highlighting| support for |haskell| sources, and
any other Haskell-related plugins you might want to install (see
|haskellmode-resources|).
The Haskell mode plugins consist of three filetype plugins (haskell.vim,
haskell_doc.vim, haskell_hpaste.vim), which by Vim's |filetype| detection
mechanism will be auto-loaded whenever files with the extension '.hs' are
opened, and one compiler plugin (ghc.vim) which you will need to load from
your vimrc file (see |haskellmode-settings|).
*haskellmode-requirements*
1.1 Runtime Requirements ~
The plugins require a recent installation of GHC/GHCi. The functionality
derived from Haddock-generated library indices also requires a local
installation of the Haddock documentation for GHC's libraries (if there is
no documentation package for your system, you can download a tar-ball from
haskell.org), as well as an HTML browser (see |haddock_browser|). If you
want to use the experimental hpaste interface, you will also need Wget.
* GHC/GHCi ~
Provides core functionality. http://www.haskell.org/ghc
* HTML library documentation files and indices generated by Haddock ~
These usually come with your GHC installation, possibly as a separate
package. If you cannot get them this way, you can download a tar-ball
from http://www.haskell.org/ghc/docs/latest/
* HTML browser with basic CSS support ~
For browsing Haddock docs.
* Wget ~
For interfacing with http://hpaste.org.
Wget is widely available for modern Unix-like operating systems. Several
ports also exist for Windows, including:
- Official GNU Wget (natively compiled for Win32)
http://www.gnu.org/software/wget/#downloading
- UnxUtils Wget (natively compiled for Win32, bundled with other ported
Unix utilities)
http://sourceforge.net/projects/unxutils/
- Cygwin Wget (emulated POSIX in Win32, must be run under Cygwin)
http://cygwin.com/packages/wget/
*haskellmode-quickref*
1.2 Quick Reference ~
|:make| load into GHCi, show errors (|quickfix| |:copen|)
|_ct| create |tags| file
|_si| show info for id under cursor
|_t| show type for id under cursor
|_T| insert type declaration for id under cursor
|balloon| show type for id under mouse pointer
|_?| browse Haddock entry for id under cursor
|:IDoc| {identifier} browse Haddock entry for unqualified {identifier}
|:MDoc| {module} browse Haddock entry for {module}
|:FlagReference| {s} browse Users Guide Flag Reference for section {s}
|_.| qualify unqualified id under cursor
|_i| add 'import <module>(<identifier>)' for id under cursor
|_im| add 'import <module>' for id under cursor
|_ie| make imports explit for import statement under cursor
|_opt| add OPTIONS_GHC pragma
|_lang| add LANGUAGE pragma
|i_CTRL-X_CTRL-O| insert-mode completion based on imported ids (|haskellmode-XO|)
|i_CTRL-X_CTRL-U| insert-mode completion based on documented ids (|haskellmode-XU|)
|i_CTRL-N| insert-mode completion based on imported sources
|:GHCi|{command/expr} run GHCi command/expr in current module
|:GHCStaticOptions| edit static GHC options for this buffer
|:DocSettings| show current Haddock-files-related plugin settings
|:DocIndex| populate Haddock index
|:ExportDocIndex| cache current Haddock index to a file
|:HpasteIndex| Read index of most recent entries from hpaste.org
|:HpastePostNew| Submit current buffer as a new hpaste
==============================================================================
*haskellmode-settings*
2. Settings ~
The plugins try to find their dependencies in standard locations, so if
you're lucky, you will only need to set |compiler| to ghc, and configure
the location of your favourite web browser. Given the variety of things to
guess, however, some dependencies might not be found correctly, or the
defaults might not be to your liking, in which case you can do some more
fine tuning. All of this configuration should happen in your |vimrc|.
*haskellmode-settings-main*
2.1 GHC and web browser ~
*compiler-ghc* *ghc-compiler*
To use the features provided by the GHC |compiler| plugin, use the
following |autocommand| in your vimrc:
>
au BufEnter *.hs compiler ghc
<
*g:ghc*
If the compiler plugin can't locate your GHC binary, or if you have
several versions of GHC installed and have a preference as to which binary
is used, set |g:ghc|:
>
:let g:ghc="/usr/bin/ghc-6.6.1"
<
*:GHCStaticOptions*
:GHCStaticOptions Edit the static GHC options for the current buffer.
Useful for adding hidden packages (-package ghc).
*g:haddock_browser*
The preferred HTML browser for viewing Haddock documentation can be set as
follows:
>
:let g:haddock_browser="/usr/bin/firefox"
<
*haskellmode-settings-fine*
2.2 Fine tuning - more configuration options ~
Most of the fine tuning is likely to happen for the haskellmode_doc.vim
plugin, so you can check the current settings for this plugin via the
command |:DocSettings|. If all the settings reported there are to your
liking, you probably won't need to do any fine tuning.
*g:haddock_browser_callformat*
By default, the web browser|g:haddock_browser| will be started
asynchronously (in the background) on Windows or when vim is running in a
GUI, and synchronously (in the foreground) otherwise. These settings seem
to work fine if you are using a console mode browser (eg, when editing in
a remote session), or if you are starting a GUI browser that will launch
itself in the background. But if these settings do not work for you, you
can change the default browser launching behavior.
This is controlled by |g:haddock_browser_callformat|. It specifies a
format string which uses two '%s' parameters, the first representing the
path of the browser to launch, and the second is the documentation URL
(minus the protocol specifier, i.e. file://) passed to it by the Haddock
plugin. For instance, to launch a GUI browser on Unix-like systems and
force it to the background (see also |shellredir|):
>
:let g:haddock_browser_callformat = '%s file://%s '.printf(&shellredir,'/dev/null').' &'
<
*g:haddock_docdir*
Your system's installed Haddock documentation for GHC and its libraries
should be automatically detected. If the plugin can't locate them, you
must point |g:haddock_docdir| to the path containing the master index.html
file for the subdirectories 'libraries', 'Cabal', 'users_guide', etc.:
>
:let g:haddock_docdir="/usr/local/share/doc/ghc/html/"
<
*g:haddock_indexfiledir*
The information gathered from Haddock's index files will be stored in a
file called 'haddock_index.vim' in a directory derived from the Haddock
location, or in $HOME. To configure another directory for the index file,
use:
>
:let g:haddock_indexfiledir="~/.vim"
<
*g:wget*
If you also want to try the experimental hpaste functionality, you might
you need to set |g:wget| before the |hpaste| plugin is loaded (unless wget
is in your PATH):
>
:let g:wget="C:\Program Files\wget\wget.exe"
<
Finally, the mappings actually use|<LocalLeader>|behind the scenes, so if
you have to, you can redefine|maplocalleader|to something other than '_'.
Just remember that the docs still refer to mappings starting with '_', to
avoid confusing the majority of users!-)
==============================================================================
*haskellmode-compiler* *ghc*
3. GHC Compiler Integration ~
The GHC |compiler| plugin sets the basic |errorformat| and |makeprg| to
enable |quickfix| mode using GHCi, and provides functionality for show
info (|_si|), show type (|_t| or mouse |balloon|), add type declaration
(|_T|), create tag file (|_ct|), and insert-mode completion
(|i_CTRL-X_CTRL-O|) based on GHCi browsing of the current and imported
modules.
To avoid frequent calls to GHCi, type information is cached in Vim. The
cache will be populated the first time a command depends on it, and will
be refreshed every time a |:make| goes through without generating errors
(if the |:make| does not succeed, the old types will remain available in
Vim). You can also unconditionally force reloading of type info using
|:GHCReload| (if GHCi cannot load your file, the type info will be empty).
In addition to the standard|quickfix| commands, the GHC compiler plugin
provides:
*:GHCReload*
:GHCReload Reload modules and unconditionally refresh cache of
type info. Usually, |:make| is prefered, as that will
refresh the cache only if GHCi reports no errors, and
show the errors otherwise.
*:GHCi*
:GHCi {command/expr} Run GHCi commands/expressions in the current module.
*_ct*
_ct Create |tags| file for the current Haskell source
file. This uses GHCi's :ctags command, so it will work
recursively, but will only list tags for exported
entities.
*_opt*
_opt Shows a menu of frequently used GHC compiler options
(selecting an entry adds the option as a pragma to the
start of the file). Uses popup menu (GUI) or :emenu
and command-line completion (CLI).
*_lang*
_lang Shows a menu of the LANGUAGE options supported by GHC
(selecting an entry adds the language as a pragma to
the start of the file). Uses popup menu (GUI) or
:emenu and command-line completion (CLI).
*_si*
_si Show extended information for the name under the
cursor. Uses GHCi's :info command.
*_t*
_t Show type for the name under the cursor. Uses cached
info from GHCi's :browse command.
*_T*
_T Insert type declaration for the name under the cursor.
Uses cached info from GHCi's :browse command.
*haskellmode-XO* *haskellmode-omni-completion*
CTRL-X CTRL-O Standard insert-mode omni-completion based on the
cached type info from GHCi browsing current and
imported modules. Only names from the current and from
imported modules are included (the completion menu
also show the type of each identifier).
==============================================================================
*haskellmode-haddock* *haddock*
4. Haddock Integration ~
Haskell mode integrates with Haddock-generated HTML documentation,
providing features such as navigating to the Haddock entry for the
identifier under the cursor (|_?|), completion for the identifier under
the cursor (|i_CTRL-X_CTRL-U|), and adding import statements (|_i| |_im|)
or module qualifier (|_.|) for the identifier under the cursor.
These commands operate on an internal Haddock index built from the
platform's installed Haddock documentation for GHC's libraries. Since
populating this index takes several seconds, it should be stored as a
file called 'haddock_index.vim' in the directory specified by
|g:haddock_indexfiledir|.
Some commands present a different interface (popup menu or command-line
completion) according to whether the current Vim instance is graphical or
console-based (actually: whether or not the GUI is running). Such
differences are marked below with the annotations (GUI) and (CLI),
respectively.
|:DocSettings| shows the settings for this plugin. If you are happy with
them, you can call |:ExportDocIndex| to populate and write out the
documentation index (should be called once for every new version of GHC).
*:DocSettings*
:DocSettings Show current Haddock-files-related plugin settings.
*haskellmode-indexing*
4.1 Indexing ~
*:DocIndex*
:DocIndex Populate the Haddock index from the GHC library
documentation.
*:ExportDocIndex*
:ExportDocIndex Cache the current Haddock index to a file (populate
index first, if empty).
*haskellmode-lookup*
4.2 Lookup ~
*_?*
_? Open the Haddock entry (in |haddock_browser|) for an
identifier under the cursor, selecting full
qualifications from a popup menu (GUI) or via
command-line completion (CLI), if the identifier is
not qualified.
*:IDoc*
:IDoc {identifier} Open the Haddock entry for the unqualified
{identifier} in |haddock_browser|, suggesting possible
full qualifications.
*:MDoc*
:MDoc {module} Open the Haddock entry for {module} in
|haddock_browser| (with command-line completion for
the fully qualified module name).
*:FlagReference*
:FlagReference {s} Browse Users Guide Flag Reference for section {s}
(with command-line completion for section headers).
*haskellmode-editing*
4.3 Editing ~
*_.*
_. Fully qualify the unqualified name under the cursor
selecting full qualifications from a popup menu (GUI)
or via command-line completion (CLI).
*_i*
_i Add 'import <module>(<identifier>)' statement for the
identifier under the cursor, selecting fully qualified
modules from a popup menu (GUI) or via command-line
completion (CLI), if the identifier is not qualified.
This currently adds one import statement per call
instead of merging into existing import statements.
*_im*
_im Add 'import <module>' statement for the identifier
under the cursor, selecting fully qualified modules
from a popup menu (GUI) or via command-line completion
(CLI), if the identifier is not qualified. This
currently adds one import statement per call instead
of merging into existing import statements.
*_ie*
_ie On an 'import <module>' line, in a correctly loadable
module, temporarily comment out import and use :make
'not in scope' errors to explicitly list imported
identifiers.
*haskellmode-XU* *haskellmode-user-completion*
CTRL-X CTRL-U User-defined insert mode name completion based on all
names known to the Haddock index, including package
names. Completions are presented in a popup menu which
also displays the fully qualified module from which
each entry may be imported.
CamelCode shortcuts are supported, meaning that
lower-case letters can be elided, using only
upper-case letters and module qualifier separators (.)
for disambiguation:
pSL -> putStrLn
C.E.t -> Control.Exception.t
C.M.MP -> Control.Monad.MonadPlus
To reduce unwanted matches, the first letter of such
shortcuts and the first letter after each '.' have to
match directly.
==============================================================================
*haskellmode-hpaste* *hpaste*
5. Hpaste Integration ~
This experimental feature allows browsing and posting to
http://hpaste.org, a Web-based pastebin tailored for Haskell code.
*:HpasteIndex*
:HpasteIndex Read the most recent entries from hpaste.org. Show an
index of the entries in a new buffer, where ',r' will
open the current highlighted entry and ',p' will
annotate it with the current buffer.
*:HpastePostNew*
:HpastePostNew Submit current buffer as a new hpaste entry.
==============================================================================
*haskellmode-resources*
6. Additional Resources ~
An illustrated walk-through of these plugins is available at:
http://www.cs.kent.ac.uk/people/staff/cr3/toolbox/haskell/Vim/vim.html
Other Haskell-related Vim plugins can be found here:
http://www.haskell.org/haskellwiki/Libraries_and_tools/Program_development#Vim
Make sure to read about Vim's other program-editing features in its online
|user-manual|. Also have a look at Vim tips and plugins at www.vim.org -
two other plugins I tend to use when editing Haskell are AlignPlugin.vim
(to line up regexps for definitions, keywords, comments, etc. in
consecutive lines) and surround.vim (to surround text with quotes,
brackets, parentheses, comments, etc.).
==============================================================================
vim:tw=78:ts=8:ft=help: