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Latest commit 04b0b39 @dleslie dleslie Fuzzy matching for Chicken AutoDoc and Completions
Because Chicken allows symbols to be imported with prefixes, and because
'apropos' does not provide any utility to match with the loaded
prefixes, it is difficult to acquire information about prefixed symbols.

This solution hacks around the issue by providing naive
fuzzy-matching. If no match for a symbol can be found then the first
character is dropped and matching is attempted again; the process is
repeated until matches are found or the entire symbol is consumed.

Also removes the (now redundant and slow) geiser-chicken-prefix-delimiters.


* Overview

  Geiser is a generic Emacs/Scheme interaction mode, featuring an
  enhanced REPL and a set of minor modes improving Emacs' basic scheme
  major mode. The main functionalities provided are:

    - Evaluation of forms in the namespace of the current module.
    - Macro expansion.
    - File/module loading.
    - Namespace-aware identifier completion (including local bindings,
      names visible in the current module, and module names).
    - Autodoc: the echo area shows information about the signature of
      the procedure/macro around point automatically.
    - Jump to definition of identifier at point.
    - Access to documentation (including docstrings when the
      implementation provides it).
    - Listings of identifiers exported by a given module.
    - Listings of callers/callees of procedures.
    - Rudimentary support for debugging (list of
      evaluation/compilation error in an Emacs' compilation-mode
    - Support for inline images in schemes, such as Racket, that treat
      them as first order values.

   NOTE: if you're not in a hurry, Geiser's website
   ( contains a nicer manual, also
   included in Geiser tarballs as a texinfo file (doc/

* Requirements

    Geiser needs Emacs 23.2 or better, and at least one of the
    supported scheme implementations:
      - Guile 2.0 or better.
      - PLT Racket 6.0 or better.
      - Chicken 4.8.0 or better.

* Installation

  The easiest way is to use ELPA/Marmalade, and just type
  `M-x install-package RET geiser` inside emacs.

  Geiser can be used either directly from its uninstalled source tree
  or byte-compiled and installed after performing the standard
  configure/make/make install dance.  See the INSTALL file for more details.

** Chicken Addendum
    These steps are necessary to fully support Chicken Scheme, but are
    not required for any other scheme.

    - Install the necessary support eggs:
      $ chicken-install -s apropos chicken-doc
    - Update the Chicken documentation database:
      $ cd `csi -p '(chicken-home)'`
      $ curl | sudo tar zx

* Basic configuration

  The loading invocations above install all supported Scheme
  implementations. You can list explicitly the ones that you want by
  setting the variable `geiser-active-implementations' *before*
  loading geiser.el. For instance:

  (setq geiser-active-implementations '(chicken guile))

   On opening a scheme file, Geiser will try to guess its Scheme,
   defaulting to the first in the list. Use `C-c C-s' to select the
   implementation by hand (on a per file basis).

  Check the geiser customization group for some options with:

      M-x customize-group RET geiser RET

  In particular, customize `geiser-<impl>-binary', which should point
  to an executable in your path.

  To start a REPL, M-x geiser.

** Completion with company-mode

    Geiser offers identifier and module name completion, bound to
    M-TAB and M-` respectively. Only names visible in the current
    module are offered.

    While that is cool and all, things are even better: if you have
    company-mode ( installed,
    Geiser's completion will use it. Just require company-mode and,
    from then on, any new scheme buffer or REPL will use it.

* Quick key reference

** In Scheme buffers:

    | C-c C-z     | Switch to REPL                                  |
    | C-c C-a     | Switch to REPL and current module               |
    | C-c C-s     | Specify Scheme implementation for buffer        |
    | M-.         | Go to definition of identifier at point         |
    | M-,         | Go back to where M-. was last invoked           |
    | C-c C-e m   | Ask for a module and open its file              |
    | C-c C-e C-l | Add a given directory to Scheme's load path     |
    | C-c C-e [   | Toggle between () and [] for current form       |
    | C-M-x       | Eval definition around point                    |
    | C-c M-e     | Eval definition around point and switch to REPL |
    | C-x C-e     | Eval sexp before point                          |
    | C-c C-r     | Eval region                                     |
    | C-c M-r     | Eval region and switch to REPL                  |
    | C-c C-b     | Eval buffer                                     |
    | C-c M-b     | Eval buffer and switch to REPL                  |
    | C-c C-m x   | Macro-expand definition around point            |
    | C-c C-m e   | Macro-expand sexp before point                  |
    | C-c C-m r   | Macro-expand region                             |
    | C-c C-k     | Compile and load current file                   |
    | C-c C-d d   | See documentation for identifier at point       |
    | C-c C-d s   | See short documentation for identifier at point |
    | C-c C-d i   | Look up manual for identifier at point          |
    | C-c C-d m   | See a list of a module's exported identifiers   |
    | C-c C-d a   | Toggle autodoc mode                             |
    | C-c <       | Show callers of procedure at point              |
    | C-c >       | Show callees of procedure at point              |
    | M-TAB       | Complete identifier at point                    |
    | M-`, C-.    | Complete module name at point                   |
    | TAB         | Complete identifier at point or indent          |
    |             | (If `geiser-mode-smart-tab-p' is t)             |

** In the REPL

    | C-c C-z     | Start Scheme REPL, or jump to previous buffer      |
    | C-c M-o     | Clear scheme output                                |
    | C-c C-q     | Kill Scheme process                                |
    | C-c C-k     | Nuke REPL: use it if the REPL becomes unresponsive |
    | M-.         | Edit identifier at point                           |
    | TAB, M-TAB  | Complete identifier at point                       |
    | M-`, C-.    | Complete module name at point                      |
    | M-p, M-n    | Prompt history, matching current prefix            |
    | C-c C-m     | Set current module                                 |
    | C-c C-i     | Import module into current namespace               |
    | C-c C-r     | Add a given directory to scheme's load path        |
    | C-c C-d C-d | See documentation for symbol at point              |
    | C-c C-d C-m | See documentation for module                       |
    | C-c C-d C-a | Toggle autodoc mode                                |

** In the documentation browser:

    | f        | Next page                                    |
    | b        | Previous page                                |
    | TAB, n   | Next link                                    |
    | S-TAB, p | Previous link                                |
    | N        | Next section                                 |
    | P        | Previous section                             |
    | k        | Kill current page and go to previous or next |
    | g, r     | Refresh page                                 |
    | c        | Clear browsing history                       |
    | ., M-.   | Edit identifier at point                     |
    | z        | Switch to REPL                               |
    | q        | Bury buffer                                  |

** In backtrace (evaluation/compile result) buffers:

    - M-g n, M-g p, C-x ` for error navigation.
    - q to bury buffer.
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