*if_mzsch.txt*  For Vim version 7.2.  Last change: 2008 Jun 28


		  VIM REFERENCE MANUAL    by Sergey Khorev


The MzScheme Interface to Vim				*mzscheme* *MzScheme*

1. Commands				|mzscheme-commands|
2. Examples				|mzscheme-examples|
3. Threads				|mzscheme-threads|
4. The Vim access procedures		|mzscheme-vim|
5. Dynamic loading			|mzscheme-dynamic|

{Vi does not have any of these commands}

The MzScheme interface is available only if Vim was compiled with the
|+mzscheme| feature.

Based on the work of Brent Fulgham.
Dynamic loading added by Sergey Khorev

For downloading MzScheme and other info:
	http://www.plt-scheme.org/software/mzscheme/

Note: On FreeBSD you should use the "drscheme" port.

==============================================================================
1. Commands						*mzscheme-commands*

							*:mzscheme* *:mz*
:[range]mz[scheme] {stmt}
			Execute MzScheme statement {stmt}.  {not in Vi}

:[range]mz[scheme] << {endmarker}
{script}
{endmarker}
			Execute inlined MzScheme script {script}.
			Note: This command doesn't work if the MzScheme
			feature wasn't compiled in.  To avoid errors, see
			|script-here|.

							*:mzfile* *:mzf*
:[range]mzf[ile] {file}	Execute the MzScheme script in {file}.  {not in Vi}
			All statements are executed in the namespace of the
			buffer that was current during :mzfile start.
			If you want to access other namespaces, use
			'parameterize'.

All of these commands do essentially the same thing - they execute a piece of
MzScheme code, with the "current range" set to the given line
range.

In the case of :mzscheme, the code to execute is in the command-line.
In the case of :mzfile, the code to execute is the contents of the given file.

Each buffer has its own MzScheme namespace. Global namespace is bound to
the "global-namespace" value from the 'vimext' module.
MzScheme interface defines exception exn:vim, derived from exn.
It is raised for various Vim errors.

During compilation, the MzScheme interface will remember the current MzScheme
collection path. If you want to specify additional paths use the
'current-library-collection-paths' parameter. E.g., to cons the user-local
MzScheme collection path: >
    :mz << EOF
    (current-library-collection-paths
	(cons
	    (build-path (find-system-path 'addon-dir) (version) "collects")
	    (current-library-collection-paths)))
    EOF
<

All functionality is provided through module vimext.

The exn:vim is available without explicit import.

To avoid clashes with MzScheme, consider using prefix when requiring module,
e.g.: >
	:mzscheme (require (prefix vim- vimext))
<
All the examples below assume this naming scheme.  Note that you need to do
this again for every buffer.

The auto-instantiation can be achieved with autocommands, e.g. you can put
something like this in your .vimrc (EOFs should not have indentation): >
    function s:MzRequire()
	if has("mzscheme")
	    :mz << EOF
	    (require (prefix vim- vimext))
	    (let ((buf (vim-get-buff-by-name (vim-eval "expand(\"<afile>\")"))))
	      (when (and buf (not (eq? buf (vim-curr-buff))))
		(parameterize ((current-namespace (vim-get-buff-namespace buf)))
		  (namespace-attach-module vim-global-namespace 'vimext)
		  (namespace-require '(prefix vim vimext)))))
    EOF
	endif
    endfunction

    function s:MzStartup()
	if has("mzscheme")
	    au BufNew,BufNewFile,BufAdd,BufReadPre * :call s:MzRequire()
	    :mz << EOF
	    (current-library-collection-paths
		(cons
		    (build-path (find-system-path 'addon-dir) (version) "collects")
		    (current-library-collection-paths)))
    EOF
	endif
    endfunction

    call s:MzStartup()
<

The global namespace just instantiated this module with the prefix "vimext:".
							*mzscheme-sandbox*
When executed in the |sandbox|, access to some filesystem and Vim interface
procedures is restricted.

==============================================================================
2. Examples						*mzscheme-examples*
>
	:mzscheme (display "Hello")
	:mzscheme (vim-set-buff-line 10 "This is line #10")
<
Inline script usage: >
	function! <SID>SetFirstLine()
	    :mz << EOF
	    (display "!!!")
	    (vim-set-buff-line 1 "This is line #1")
	    (vim-beep)
	    EOF
	endfunction

	nmap <F9> :call <SID>SetFirstLine() <CR>
<
File execution: >
	:mzfile supascript.scm
<
Accessing the current buffer namespace from an MzScheme program running in
another buffer within |:mzfile|-executed script : >
	; Move to the window below
	(vim-command "wincmd j")
	; execute in the context of buffer, to which window belongs
	; assume that buffer has 'textstring' defined
	(parameterize ((current-namespace
			(vim-get-buff-namespace (vim-curr-buff))))
	 (eval '(vim-set-buff-line 1 textstring)))
<

==============================================================================
3. Threads						*mzscheme-threads*

The MzScheme interface supports threads. They are independent from OS threads,
thus scheduling is required. The option 'mzquantum' determines how often
Vim should poll for available MzScheme threads.
NOTE
Thread scheduling in the console version of Vim is less reliable than in the
GUI version.

==============================================================================
5. VIM Functions					*mzscheme-vim*

							*mzscheme-vimext*
The 'vimext' module provides access to procedures defined in the MzScheme
interface.

Common
------
    (command {command-string})	    Perform the vim ":Ex" style command.
    (eval {expr-string})	    Evaluate the vim expression to a string.
				    A |List| is turned into a string by
				    joining the items and inserting line
				    breaks.
				    NOTE clashes with MzScheme eval
    (range-start)		    Start/End of the range passed with
    (range-end)			    the Scheme command.
    (beep)			    beep
    (get-option {option-name} [buffer-or-window]) Get Vim option value (either
				    local or global, see set-option).
    (set-option {string} [buffer-or-window])
				    Set a Vim option. String must have option
				    setting form (like optname=optval, or
				    optname+=optval, etc.) When called with
				    {buffer} or {window} the local option will
				    be set. The symbol 'global can be passed
				    as {buffer-or-window}. Then |:setglobal|
				    will be used.
    global-namespace		    The MzScheme main namespace.

Buffers							 *mzscheme-buffer*
-------
    (buff? {object})		    Is object a buffer?
    (buff-valid? {object})	    Is object a valid buffer? (i.e.
				    corresponds to the real Vim buffer)
    (get-buff-line {linenr} [buffer])
				    Get line from a buffer.
    (set-buff-line {linenr} {string} [buffer])
				    Set a line in a buffer. If {string} is #f,
				    the line gets deleted.  The [buffer]
				    argument is optional. If omitted, the
				    current buffer will be used.
    (get-buff-line-list {start} {end} [buffer])
				    Get a list of lines in a buffer. {Start}
				    and {end} are 1-based. {Start} is
				    inclusive, {end} - exclusive.
    (set-buff-line-list {start} {end} {string-list} [buffer])
				    Set a list of lines in a buffer. If
				    string-list is #f or null, the lines get
				    deleted. If a list is shorter than
				    {end}-{start} the remaining lines will
				    be deleted.
    (get-buff-name [buffer])	    Get a buffer's text name.
    (get-buff-num [buffer])	    Get a buffer's number.
    (get-buff-size [buffer])	    Get buffer line count.
    (insert-buff-line-list {linenr} {string/string-list} [buffer])
				    Insert a list of lines into a buffer after
				    {linenr}. If {linenr} is 0, lines will be
				    inserted at start.
    (curr-buff)			    Get the current buffer. Use procedures
				    from "vimcmd" module to change it.
    (buff-count)		    Get count of total buffers in the editor.
    (get-next-buff [buffer])	    Get next buffer.
    (get-prev-buff [buffer])	    Get previous buffer. Return #f when there
				    are no more buffers.
    (open-buff {filename})	    Open a new buffer (for file "name")
    (get-buff-by-name {buffername}) Get a buffer by its filename or #f
					if there is no such buffer.
    (get-buff-by-num {buffernum})   Get a buffer by its number (return #f if
				    there is no buffer with this number).
    (get-buff-namespace [buffer])   Get buffer namespace.

Windows							    *mzscheme-window*
------
    (win? {object})		    Is object a window?
    (win-valid? {object})	    Is object a valid window (i.e. corresponds
				    to the real Vim window)?
    (curr-win)			    Get the current window.
    (win-count)			    Get count of windows.
    (get-win-num [window])	    Get window number.
    (get-win-by-num {windownum})    Get window by its number.
    (get-win-buffer	[window])   Get the buffer for a given window.
    (get-win-height [window])
    (set-win-height {height} [window])  Get/Set height of window.
    (get-win-width [window])
    (set-win-width {width} [window])Get/Set width of window.
    (get-win-list [buffer])	    Get list of windows for a buffer.
    (get-cursor [window])	    Get cursor position in a window as
				    a pair (linenr . column).
    (set-cursor (line . col) [window])  Set cursor position.

==============================================================================
5. Dynamic loading					*mzscheme-dynamic*

On MS-Windows the MzScheme libraries can be loaded dynamically. The |:version|
output then includes |+mzscheme/dyn|.

This means that Vim will search for the MzScheme DLL files only when needed.
When you don't use the MzScheme interface you don't need them, thus you can
use Vim without these DLL files.

To use the MzScheme interface the MzScheme DLLs must be in your search path.
In a console window type "path" to see what directories are used.

The names of the DLLs must match the MzScheme version Vim was compiled with.
For MzScheme version 209 they will be "libmzsch209_000.dll" and
"libmzgc209_000.dll". To know for sure look at the output of the ":version"
command, look for -DDYNAMIC_MZSCH_DLL="something" and
-DDYNAMIC_MZGC_DLL="something" in the "Compilation" info.

======================================================================
  vim:tw=78:ts=8:sts=4:ft=help:norl:
