Font file loading information

The information which tells L^ATEX exactly which font (.tfm) files to load is contained in the <loading-info> part of a \DeclareFontShape declaration. This part consists of one or more <fontshape-decl>s, each of which has the following form:

<fontshape-decl>	$::=$	<size-infos> <font-info>
<size-infos>	$::=$	<size-infos> <size-info> $\mid$ <size-info>
<size-info>	$::=$	``<<'' <number-or-range> ``>>''
<font-info>	$::=$	[ <size-function> ``*'' ] [ ``['' <optarg> ``]'' ] <fontarg>

The <number-or-range> denotes the size or size-range for which this entry applies. If it contains a hyphen it is a range: lower bound on the left (if missing, zero implied), upper bound on the right (if missing, $\infty$ implied). For ranges, the upper bound is not included in the range and the lower bound is. Examples:

<<10>>	simple size	10pt only
<<-8>>	range	all sizes less than 8pt
<<8-14.4>>	range	all sizes greater than or equal to 8pt
		but less than 14.4pt
<<14.4->>	range	all sizes greater than or equal 14.4pt

If more than one <size-info> entry follows without any intervening <font-info>, they all share the next <font-info>. The <size-function>, if present, handles the use of <font-info>. If not present, the `empty' <size-function> is assumed. All the <size-info>s are inspected in the order in which they appear in the font shape declaration. If a <size-info> matches the requested size, its <size-function> is executed. If \external@font is non-empty afterwards this process stops, otherwise the next <size-info> is inspected. (See also \DeclareSizeFunction.) If this process does not lead to a non-empty \external@font, L^ATEX tries the nearest simple size. If the entry contains only ranges an error is returned.