1. Module (chicken csi)
    1. toplevel-command
    2. set-describer!
    3. default-evaluator
    4. editor-command

Module (chicken csi)

This module provides procedures to access features specific to the csi interactive interpreter.

toplevel-command

[procedure] (toplevel-command SYMBOL PROC [HELPSTRING])

Defines or redefines a toplevel interpreter command which can be invoked by entering ,SYMBOL. PROC will be invoked when the command is entered and may read any required argument via read (or read-line). If the optional argument HELPSTRING is given, it will be listed by the ,? command.

set-describer!

[procedure] (set-describer! TAG PROC)

Sets a custom description handler that invokes PROC when the ,d command is invoked with a record-type object that has the type TAG (a symbol). PROC is called with two arguments: the object to be described and an output-port. It should write a possibly useful textual description of the object to the passed output-port. For example:

#;1> (define-record-type point (make-point x y) point?
       (x point-x)
       (y point-y))
#;2> (set-describer! 'point 
       (lambda (pt o)
         (with-output-to-port o
           (lambda ()
             (print "a point with x=" (point-x pt) " and y=" (point-y pt))))))
#;3> ,d (make-point 1 2)
a point with x=1 and y=2

default-evaluator

[procedure] (default-evaluator EXPR)

Takes EXPR and processes any of the built-in toplevel commands provided by csi. If EXPR is not a toplevel command, then it is evaluated using eval. This procedure is intended to be passed as an argument to repl to allow using csis toplevel commands and history management in user-defined read-eval-print loops.

editor-command

[parameter] editor-command

Holds the name of an editor that should be used when the toplevel command ,e is used.

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