26 Scheme

scheme:sexp-snip<%> : interface?

(send a-scheme:sexp-snip get-saved-snips) → (listof snip%)

This returns the list of snips hidden by the sexp snip.

scheme:sexp-snip% : class?

superclass: snip%

extends:  scheme:sexp-snip<%>   readable-snip<%>

(send a-scheme:sexp-snip get-text   offset             num            [ flattened?])   →   string

offset : number

num : number

flattened? : boolean = |#f|

Overrides get-text in snip%.

Returns the concatenation of the text for all of the hidden snips.

(send a-scheme:sexp-snip copy) → (is-a?/c scheme:sexp-snip%)

Overrides copy in snip%.

Returns a copy of this snip that includes the hidden snips.

(send a-scheme:sexp-snip write stream-out) → void

stream-out : editor-stream-out%

Overrides write in snip%.

Saves the embedded snips

(send a-scheme:sexp-snip draw   dc             x             y             left             top             right             bottom             dx             dy             draw-caret)   →   void

dc : dc<%>

x : real

y : real

left : real

top : real

right : real

bottom : real

dx : real

dy : real

draw-caret : symbol?

Overrides draw in snip%.

Draws brackets with a centered ellipses between them.

(send a-scheme:sexp-snip get-extent   dc             x             y            [ w             h             descent             space             lspace             rspace])   →   void

dc : (is-a?/c dc<%>)

x : real

y : real

w : boxed = |#f|

h : boxed = |#f|

descent : boxed = |#f|

space : boxed = |#f|

lspace : boxed = |#f|

rspace : boxed = |#f|

Overrides get-extent in snip%.

Returns a size corresponding to what this snip draws.

scheme:text<%> : interface?

implements:  text:basic<%>   mode:host-text<%>   color:text<%>

Texts matching this interface support Scheme mode operations.

(send a-scheme:text get-limit start) → int

start : exact-integer

Returns a limit for backward-matching parenthesis starting at position start.

(send a-scheme:text balance-parens key-event) → void

key-event : (instance key-event%)

This function is called when the user types a close parenthesis in the text%. If the close parenthesis that the user inserted does not match the corresponding open parenthesis and the 'framework:fixup-parens preference is #t (see preferences:get) the correct closing parenthesis is inserted. If the 'framework:paren-match preference is #t (see preferences:get) the matching open parenthesis is flashed.

(send a-scheme:text tabify-on-return?) → boolean?

The result of this method is used to determine if the return key automatically tabs over to the correct position.

Override it to change its behavior.

(send a-scheme:text tabify [start-pos]) → void

start-pos   :   exact-integer       =   (send this text get-start-position)

Tabs the line containing by start-pos

(send a-scheme:text tabify-selection   start             end)   →   void

start : exact-integer

end : exact-integer

Sets the tabbing for the lines containing positions start through end.

(send a-scheme:text tabify-all) → void

Tabs all lines.

(send a-scheme:text insert-return) → void

Inserts a newline into the buffer. If tabify-on-return? returns #t, this will tabify the new line.

(send a-scheme:text box-comment-out-selection   start-pos             end-pos)   →   void

start-pos : (or/c (symbols 'start) exact-integer?)

end-pos : (or/c (symbols 'end) exact-integer?)

This method comments out a selection in the text by putting it into a comment box.

Removes the region from start-pos to end-pos from the editor and inserts a comment box with that region of text inserted into the box.

If start-pos is 'start, the starting point of the selection is used. If end-pos is 'end, the ending point of the selection is used.

(send a-scheme:text comment-out-selection   start             end)   →   void

start : exact-integer

end : exact-integer

Comments the lines containing positions start through end by inserting a semi-colon at the front of each line.

(send a-scheme:text uncomment-selection   start             end)   →   void

start : int

end : int

Uncomments the lines containing positions start through end.

(send a-scheme:text get-forward-sexp start)

→ (union |#f| exact-integer)

start : exact-integer

Returns the position of the end of next S-expression after position start, or #f if there is no appropriate answer.

(send a-scheme:text remove-sexp start) → void

start : exact-integer

Forward-deletes the S-expression starting after the position start.

(send a-scheme:text forward-sexp start) → exact-integer

start : |#t|

Moves forward over the S-expression starting at position start.

(send a-scheme:text flash-forward-sexp start-pos) → void

start-pos : exact-integer

Flashes the parenthesis that closes the sexpression at start-pos.

(send a-scheme:text get-backward-sexp start)

→ (union exact-integer |#f|)

start : exact-integer

Returns the position of the start of the S-expression before or containing start, or #f if there is no appropriate answer.

(send a-scheme:text flash-backward-sexp start-pos) → void

start-pos : exact-integer

Flashes the parenthesis that opens the sexpression at start-pos.

(send a-scheme:text backward-sexp start-pos) → void

start-pos : exact-integer

Move the caret backwards one sexpression

Moves the caret to the beginning of the sexpression that ends at start-pos.

(send a-scheme:text find-up-sexp start-pos)

→ (union |#f| exact-integer)

start-pos : exact-integer

Returns the position of the beginning of the next sexpression outside the sexpression that contains start-pos. If there is no such sexpression, it returns #f.

(send a-scheme:text up-sexp start) → void

start : exact-integer

Moves backward out of the S-expression containing the position start.

(send a-scheme:text find-down-sexp start-pos)

→ (union |#f| exact-integer)

start-pos : exact-integer

Returns the position of the beginning of the next sexpression inside the sexpression that contains start-pos. If there is no such sexpression, it returns #f.

(send a-scheme:text down-sexp start) → void

start : exact-integer

Moves forward into the next S-expression after the position start.

(send a-scheme:text remove-parens-forward start) → void

start : exact-integer

Removes the parentheses from the S-expression starting after the position start.

(send a-scheme:text select-forward-sexp start) → |#t|

start : exact-integer

Selects the next S-expression, starting at position start.

(send a-scheme:text select-backward-sexp start) → |#t|

start : exact-integer

Selects the previous S-expression, starting at position start.

(send a-scheme:text select-up-sexp start) → |#t|

start : exact-integer

Selects the region to the enclosing S-expression, starting at position start.

(send a-scheme:text select-down-sexp start) → |#t|

start : exact-integer

Selects the region to the next contained S-expression, starting at position start.

(send a-scheme:text transpose-sexp start) → void

start : exact-integer

Swaps the S-expression beginning before the position start with the next S-expression following start.

(send a-scheme:text mark-matching-parenthesis pos) → void

pos : exact-positive-integer

If the paren after pos is matched, this method highlights it and its matching counterpart in dark green.

(send a-scheme:text get-tab-size) → exact-integer

This method returns the current size of the tabs for scheme mode. See also set-tab-size.

(send a-scheme:text set-tab-size new-size) → void

new-size : exact-integer

This method sets the tab size for this text.

(send a-scheme:text introduce-let-ans) → void

Adds a let around the current s-expression and a printf into the body of the let.

(send a-scheme:text move-sexp-out) → void

Replaces the sexpression surrounding the insertion point with the sexpression following the insertion point.

scheme:text-mixin : (class? . -> . class?)

argument extends/implements:  text:basic<%>   mode:host-text<%>   color:text<%>   text:autocomplete<%>

result implements:  scheme:text<%>

This mixin adds functionality for editing Scheme files.

The result of this mixin uses the same initialization arguments as the mixin’s argument.

(send a-scheme:text get-word-at pos) → string

pos : positive-exact-integer

Overrides get-word-at in text:autocomplete<%>.

Returns the word just before pos, which is then used as the prefix for auto-completion.

scheme:text-mode<%> : interface?

The result of scheme:text-mode-mixin implements this interface.

scheme:text-mode-mixin : (class? . -> . class?)

argument extends/implements:  color:text-mode<%>   mode:surrogate-text<%>

result implements:  scheme:text-mode<%>

This mixin adds Scheme mode functionality to the mode that it is mixed into. The resulting mode assumes that it is only set to an editor that is the result of scheme:text-mixin.

(send a-scheme:text-mode on-disable-surrogate) → void

Overrides on-disable-surrogate in mode:surrogate-text<%>.

Removes the scheme keymap (see also scheme:get-keymap) and disables any parenthesis highlighting in the host editor.

(send a-scheme:text-mode on-enable-surrogate) → void

Overrides on-enable-surrogate in mode:surrogate-text<%>.

Adds the scheme keymap (see also scheme:get-keymap) and enables a parenthesis highlighting in the host editor.

scheme:set-mode-mixin : (class? . -> . class?)

argument extends/implements:  scheme:text<%>   mode:host-text<%>

This mixin creates a new instance of scheme:text-mode% and installs it, by calling its own set-surrogate method with the object.

scheme:text% : class?

superclass: (scheme:set-mode-mixin (scheme:text-mixin (text:autocomplete-mixin (mode:host-text-mixin color:text%))))

scheme:text-mode% : class?

superclass: (scheme:text-mode-mixin color:text-mode%)

(scheme:text-balanced? text [start end]) → boolean?

text : (is-a?/c text%)

start : number? = 0

end : (or/c false/c number?) = #f

Determines if the range in the editor from start to end in text is a matched set of parenthesis. If end is #f, it defaults to the last position of the text.

The implementation of this function creates a port with open-input-text-editor and then uses `read’ to parse the range of the buffer.

(scheme:add-preferences-panel) → void?

Adds a tabbing preferences panel to the preferences dialog.

(scheme:get-keymap) → (is-a?/c keymap%)

Returns a keymap with binding suitable for Scheme.

(scheme:add-coloring-preferences-panel) → any

Installs the “Scheme” preferences panel in the “Syntax Coloring” section.

(scheme:get-color-prefs-table)

→ (listof (list/c symbol? (is-a?/c color%)))

Returns a table mapping from symbols (naming the categories that the online colorer uses for Scheme mode coloring) to their colors.

These symbols are suitable for input to scheme:short-sym->pref-name and scheme:short-sym->style-name.

See also scheme:get-white-on-black-color-prefs-table.

(scheme:get-white-on-black-color-prefs-table)

→ (listof (list/c symbol? (is-a?/c color%)))

Returns a table mapping from symbols (naming the categories that the online colorer uses for Scheme mode coloring) to their colors when the user chooses the white-on-black mode in the preferences dialog.

See also scheme:get-color-prefs-table.

(scheme:short-sym->pref-name short-sym) → symbol?

short-sym : symbol?

Builds the symbol naming the preference from one of the symbols in the table returned by scheme:get-color-prefs-table.

(scheme:short-sym->style-name short-sym) → string?

short-sym : symbol?

Builds the symbol naming the editor style from one of the symbols in the table returned by scheme:get-color-prefs-table. This style is a named style in the style list returned by editor:get-standard-style-list.

(scheme:get-wordbreak-map) → (is-a?/c editor-wordbreak-map%)

This method returns a #<procedure:link> editor-wordbreak-map that is suitable for Scheme.

(scheme:init-wordbreak-map key) → void?

key : (is-a?/c keymap%)

Initializes the workdbreak map for keymap.

(scheme:setup-keymap keymap) → void?

keymap : (is-a?/c keymap%)

Initializes keymap with Scheme-mode keybindings.