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number-snip:  snip-class%
read
number-snip:  number->string/  snip
number-snip:  make-pretty-print-size
number-snip:  make-repeating-decimal-snip
number-snip:  make-fraction-snip
number-snip:  is-number-snip?
number-snip:  get-number
number-snip:  remove-decimal-looking-number-snips-on-insertion-mixin

23 Number Snip

class

number-snip:snip-class% : class?

  superclass: snip-class%

method

(send a-number-snip:snip-class read f)

  (or/c (is-a?/c snip%) #f)
  f : (is-a?/c editor-stream-in%)
Overrides read in snip-class%.
Constructs a number snip from its input.

procedure

(number-snip:number->string/snip 
  num 
  [#:exact-prefix exact-prefix 
  #:inexact-prefix inexact-prefix 
  #:fraction-view fraction-view]) 
  (or/c number-snip:is-number-snip? string?)
  num : number?
  exact-prefix : (or/c 'always 'never 'when-necessary) = 'never
  inexact-prefix : (or/c 'always 'never 'when-necessary)
   = 'never
  fraction-view : (or/c #f 'mixed 'improper 'decimal) = #f
For a number num, returns a number snip or a string according to the specified format arguments.

The exact-prefix argument specifies whether the representation should carry a #e prefix: Always, never, or when necessary to identify a representation that would otherwise be considered inexact.

Similarly for inexact-prefix. Note however that 'when-necessary is usually equivalent to 'never, as inexact numbers are always printed with a decimal dot, which is sufficient to identify a number representation as inexact.

The fraction-view field specifies how exact non-integer reals - fractions - should be rendered: As a mixed fraction, an improper fraction, or a decimal, possibly identifying periodic digits. For 'decimal, if it’s not possible to render the number as a decimal exactly, a fraction representation might be generated. This is currently the case for complex numbers.

If fraction-view is #f, this option comes from the 'framework:fraction-snip-style preference.

procedure

(number-snip:make-pretty-print-size 
  [#:exact-prefix exact-prefix 
  #:inexact-prefix inexact-prefix 
  #:fraction-view fraction-view]) 
  (number? boolean? output-port? . -> . exact-nonnegative-integer?)
  exact-prefix : (or/c 'always 'never 'when-necessary) = 'never
  inexact-prefix : (or/c 'always 'never 'when-necessary)
   = 'never
  fraction-view : (or/c #f 'mixed 'improper 'decimal) = #f
This returns a procedure usable in a pretty-print-size-hook implementation, to go with number-snip:number->string/snip. The arguments are as with number-snip:number->string/snip.

procedure

(number-snip:make-repeating-decimal-snip num 
  show-prefix?) 
  number-snip:is-number-snip?
  num : real?
  show-prefix? : boolean?
Makes a number snip that shows the decimal expansion for number. The boolean indicates if a #e prefix appears on the number.

procedure

(number-snip:make-fraction-snip num 
  show-prefix-in-decimal-view?) 
  number-snip:is-number-snip?
  num : real?
  show-prefix-in-decimal-view? : boolean?
Makes a number snip that shows a fractional view of number. The boolean indicates if a #e prefix appears on the number, when shown in the decimal state.

procedure

(number-snip:is-number-snip? v)  boolean?

  v : any/c
Determines if v is a number snip, i.e., created by number-snip:make-fraction-snip or number-snip:make-repeating-decimal-snip.

All values that answer #t to this predicate are also snip%s.
Returns the number that this number snip displays.
Overrides the on-insert and after-insert to replace number-snip% objects that look like ASCII with their corresponding ASCII text.