5.2 Unicode

MIT/GNU Scheme implements the full Unicode character repertoire, defining predicates for Unicode characters and their associated integer values. A Unicode code point is an exact non-negative integer strictly less than #x110000. A Unicode scalar value is a Unicode code point that doesn’t fall between #xD800 inclusive and #xE000 exclusive; in other words, any Unicode code point except for the surrogate code points.

procedure: unicode-code-point? object

Returns #t if object is a Unicode code point, otherwise it returns #f.

procedure: unicode-scalar-value? object

Returns #t if object is a Unicode scalar value, otherwise it returns #f.

procedure: unicode-char? object

Returns #t if object is any character corresponding to a Unicode code point, except for those with general category other:surrogate or other:not-assigned.

procedure: char-general-category char

procedure: code-point-general-category code-point

Returns the Unicode general category of char (or code-point) as a descriptive symbol:

Category	Symbol
Lu	letter:uppercase
Ll	letter:lowercase
Lt	letter:titlecase
Lm	letter:modifier
Lo	letter:other
Mn	mark:nonspacing
Mc	mark:spacing-combining
Me	mark:enclosing
Nd	number:decimal-digit
Nl	number:letter
No	number:other
Pc	punctuation:connector
Pd	punctuation:dash
Ps	punctuation:open
Pe	punctuation:close
Pi	punctuation:initial-quote
Pf	punctuation:final-quote
Po	punctuation:other
Sm	symbol:math
Sc	symbol:currency
Sk	symbol:modifier
So	symbol:other
Zs	separator:space
Zl	separator:line
Zp	separator:paragraph
Cc	other:control
Cf	other:format
Cs	other:surrogate
Co	other:private-use
Cn	other:not-assigned