Hagen - Pragma ADE

5.8 Tracing
There are a lot of tracing options in MkIV, but most will never be seen by users. Most
are enabled using the tracker mechanism. Some have a bit more visibility and have a
dedicated command to trigger them.
When something is going terribly wrong, you will always get a message but sometimes
even an end-user has to request for more information. An example are missing
characters. There are several ways to get them reported:
\enabletrackers[fonts.missing=replace]
\enabletrackers[fonts.missing=remove]
\enabletrackers[fonts.missing]
For historic reasons we also have:
\checkcharactersinfont
\removemissingcharacters
\replacemissingcharacters
which happens automatically when you enable the tracker. There is some extra overhead
involved so you might want to turn on this feature on only if you really expect characters
not to be present.
Say that we use Latin Modern fonts and ask for some of the rare fractions:
\definedfont[lmroman10-regular*default-with-missing at 10pt]
a b c ½ ⅓ ¼ ⅕ ⅙ ⅛ Ɣ ɣ ʤ ʭ ʮ α β γ
we get this: a b c ½ ¼ . In the log file you will find something like
this:
fonts > characters > start missing characters: lmroman10-regular.otf
missing > U+00194 Ɣ LATIN CAPITAL LETTER GAMMA
missing > U+00263 ɣ LATIN SMALL LETTER GAMMA
missing > U+002A4 ʤ LATIN SMALL LETTER DEZH DIGRAPH
missing > U+002AD ʭ LATIN LETTER BIDENTAL PERCUSSIVE
missing > U+002AE ʮ LATIN SMALL LETTER TURNED H WITH FISHHOOK
missing > U+003B1 α GREEK SMALL LETTER ALPHA
missing > U+003B2 β GREEK SMALL LETTER BETA
missing > U+003B3 γ GREEK SMALL LETTER GAMMA
missing > U+02153 ⅓ VULGAR FRACTION ONE THIRD
missing > U+02155 ⅕ VULGAR FRACTION ONE FIFTH
missing > U+02159 ⅙ VULGAR FRACTION ONE SIXTH
missing > U+0215B ⅛ VULGAR FRACTION ONE EIGHTH
fonts > characters > stop missing characters
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Features