*extended-spaces* Variable

Summary

Extends the notion of space to include more than just the space character.

Package

system

Initial Value

nil

Description

When the variable *extended-spaces* is true, the concept of "space" is extended from just #\Space to include other appropriate characters. The default is nil, for ANS compliance, but we recommend that you set it to t.

This variable controls how the format directives ~:C and ~:@C output graphic characters which have an empty glyph. When this variable is t, all such characters are output using the name:

(format nil "~:C" #\No-break-space)   -> "No-Break-Space" 
(format nil "~:C" (code-char #x3000)) -> "Ideographic-Space" 

When false, only one such character is output using the name:

(format nil "~:C" #\Space)            -> "Space"
(format nil "~:C" #\No-break-space)   -> " "
(format nil "~:C" (code-char #x3000)) -> "  "

It also affects whitespace-char-p.

See also

whitespace-char-p