the software you use can probably handle the mappings internally, so that the font can
be used for Unicode text as well.
Whether you can vary the font in your text depends on the tools and data formats you
use. In plain text, there is no font variation, but word processors work with other
formats. They usually have some simple tool for, for example, selecting some words
and setting their font to something different than the surrounding text.
However, some special tricks have often been used in an attempt to extend character
repertoire by font settings. In Chapter 3, we noted that you could type, on your word
processor, the letters “abc” and then select them and use the font-changing command
to set the font to Symbol to get αβχ(i.e., three Greek lowercase letters). We analyzed
this from the viewpoint of character encoding, but here the emphasis is on comparing
such tricks with the Unicode approach.
Logically, the Symbol font is a collection of mostly wrong glyphs for characters (e.g.,
an α glyph for “a”). Of course, the same trick works for Unicode text, too, unless the
software you use refuses to perform the illogical move. After all, the Symbol font does
not contain the letters “abc,” so any request to use it for them should be ignored.
Anyway, using Unicode, such tricks are completely unnecessary and pointlessly risky.
A change of font never changes the identity of characters, in the logical sense, so even
if you see αβχ,” it’s still “abc.” This can be checked by changing the font to something
else. There’s no reason to take the slightest risk of having your data passed through
some process that changes the font and distorts what you meant. In Unicode, you
simply use the right characters, using some suitable input method. To help you in such
a conversion, Appendix A contains a table of Unicode equivalents of Symbol font
glyphs.
This should not be confused with font changes needed to make some correctly entered
characters visible. For example, if you use any of the methods described in Chapter 2
to enter the Greek letter alpha α, it might still fail to display properly. If the current font
does not contain a glyph for alpha, you need to change the font locally (or globally) to
something else, such as Arial Unicode MS—but any font containing the alpha will do.
Criticism of Unicode
Unicode has been criticized on several accounts, from very different perspectives. The
following discussion tries to summarize most of the arguments and comment on them.
The presentation is not apologetic; it will admit that there are good points in the criti-
cism.
Criticism of lack of tools for indicating semantic structures is not discussed here. It is
indirectly addressed in section “Why Not Markup in Unicode?” in Chapter 9.
Criticism of Unicode | 203

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