B.17 |
Implemented Packages |
|
HEVEA distribution includes ``.hva'' packages that are
implementations of LATEX packages.
Packages described in the ``Blue Book'' (makeidx,
ifthen, graphics ---and graphicx!---,
color, alltt) are provided. Additionnaly, quite a
few extra packages are provided. I provide no full documentation for
these packages, users should refer to the first pages of the package
documentation, which can usually be found in the book [LATEX-bis],
in your local
LATEX installation or in a TeX CTAN-archive.
At the moment, package options are not ignored.
HEVEA amsmath package defines some of the constructs of the
amsmath package. At the moment, supported constructs are
the cases
environment and matrix
environments [LATEX-bis, Section 8.4], the
environments for multi-line displayed
equations (gather
,
split
,...) [LATEX-bis, Section 8.5] and the
\numberwithin
command [LATEX-bis, Section 8.6.2].
B.17.2 |
The array and tabularx
Packages |
|
The array
package is described in
[LATEX-bis, Section 5.3] and in the local documentation of modern LATEX
installations.
It is a compatible extension of LATEX arrays (see B.10.2).
Basically, it provides new column specifications
and a \newcolumntype
construct for user-defined column
specifications.
Table 1 gives a summary of the new column
specifications and of how HEVEA
implements them.
Table 1:
Column specifications from the
array package
|
m{ width} |
|
Equivalent to the p column specification (the width
argument is ignored, entries are typeset in paragraph mode with
paragraph breaks being reduced to a single line break), except that the entries
are centered vertically. |
|
b{ width} |
|
Equivalent to the p column specification, except that the entries
are bottom-aligned vertically. |
|
>{ decl} |
|
Can be used before l , c , r ,
p{ ...} , m{ ...} or
b{ ...} .
It inserts decl in front of the entries in the corresponding
column. |
|
<{ decl} |
|
Can be used after l , c , r ,
p{ ...} , m{ ...} or
b{ ...} .
It inserts decl after entries in the corresponding
column. |
|
!{ decl} |
|
Equivalent to @{ decl} |
|
Note that centered, top-aligned or bottom-aligned
in the vertical direction, do not
have exactly the same meaning in LATEX and in HTML. However, the
aspect is the same when all columns agree w.r.t. vertical alignment.
Ordinary column types (c
, l
and r
)
do not specify vertical alignment, which therefore becomes browser
dependent.
The >{
decl}
and <{
decl}
constructs permit the encoding of TeX \cases
macro as follows:
\def\cases#1{\left\{\begin{array}{l>{$}l<{$}}#1\end{array}\right.}
(This is an excerpt of the latexcommon.hva file.)
New column specifications are defined by the \newcolumntype
construct:
\newcolumntype{
col}[
narg]{
body}
Where col is one letter, the optional narg is a
number (defaults to 0), and body is built up with
valid column specifications and macro-argument references
(#
int).
Examples are:
\newcolumntype{C}{>{\bf}c}
\newcolumntype{E}[1]{*{#1}{c}}
\begin{tabular}{CE{3}}\hline
one & two & three & four \\
five & six & seven & eight \\ \hline
\end{tabular}
The column specification
C means that entries will be typeset centered and using bold
font, while the column specifications E{
num}
stands for num centered columns. We get:
|
one |
two |
three |
four |
five |
six |
seven |
eight |
|
HEVEA implements column specifications with commands defined in the
\newcommand
style. Thus, they have the same behavior as regards
double definition, which is not performed and induces a warning
message.
Thus, a column specification that is
first defined in a macro.hva specific
file, overrides the document definition.
The tabularx
package [LATEX-bis, Section 5.3.5] provides a new tabular
environment tabularx
and a new column type X
. HEVEA
makes the former equivalent to tabular
and the latter
equivalent to p{
ignored}
. By contrast with the
subtle array formatting that the tabularx package performs,
this may seem a crude implementation. However, rendering is usually
correct, although different.
More generally and from the HTML point of view such sophisticated
formatting is browser job in the first place.
However, the HTML definition allows suggested widths or heights for
table entries and table themselves.
From HEVEA point of view, drawing the border line between what can be
specified and what can be left to the browser is not obvious at all.
At the moment HEVEA choice is not to specify too much (in
particular, all length
arguments, either to column specifications or to the arrays
themselves, are ignored). As a consequence, the final, browser viewed,
aspect of arrays will usually be different from their printed
aspect.
LATEX source and documentation.
This package enables using traditional, infix, notation for
arithmetic operations
inside the num argument to the
\setcounter{
name}{
num}
and \addtocounter{
name}{
num}
constructs (see [LATEX-bis, Section A.4])
The calc package provides a similar extension of the syntax
of the len argument to the \setlength
and
\addtolength
constructs.
HEVEA does not implement this extension, since it does not
implement length registers in the first place.
B.17.4 |
The comment Package |
|
LATEX source.
The implementation for this package provides two commands,
\excludecomment
and \includecomment
, for (re-)defining
new environments that ignore their content or that do nothing. The
comment environment is also defined as an environment of the first
kind.
B.17.5 |
Multiple Indexes with the index and multind package |
|
HEVEA supports several simultaneous indexes, following the scheme
of the
index package,
which is present in modern LATEX distributions.
This scheme is backward compatible with the standard indexing scheme
of LATEX.
Support is not complete, but the most useful commands are available.
More precisely, HEVEA knows the following commands:
- \newindex{tag}{ext}{ignored}{indexname}
-
Declare an index.
The first argument tag is a tag to select this index in other
commands; ext is the extension of the index information file
generated by LATEX (e.g., idx); ignored is ignored by
HEVEA; and indexname is the title of the index.
If given the
idx
option. HEVEA attempts to read file
mydoc.ext. There also exists a
\renewindex
commands that takes the same arguments and that can be
used to redefine previously declared indexes.
- \makeindex
- Perform
\newindex{default}{idx}{ind}{Index}
.
- \index[tag]{arg}
-
Act as the LATEX
\index
command except that the information
extracted from arg goes to the tag index.
The tag argument defaults to default
, thereby yielding
standard LATEX behavior for the \index
command without an
optional argument.
There also exists a stared-variant \index*
that Additionally
typesets arg.
- \printindex[tag]
- Compute, format and
output index whose tag is tag. The tag argument
defaults to
default
. At the moment, there is an important
difference between LATEX and HEVEA: for \printindex
to
work, if must occur after the last
occurrence of the \index
command. This is little problem in
practise, since indexes usually reside at the end of books.
The multind package provides another scheme
for multiple indexes.
Note that the ``multind''
style for indexes is not backward compatible with
LATEX default indexing scheme. I would recommend using
the ``index'' package.
LATEX source.
This package in fact provides a enhanced \verb
command that
can appear inside other command arguments.
This command is named ``\url
'',
but it can be used for any verbatim text, including DOS-like path
names.
Hence, one can insert urls in one's document without worrying about
LATEX active characters :
This is a complicated url: \url{http://foo.com/~user#label%coucou}.
which gets typeset as: ``This is a complicated url: http://foo.com/~user#label%coucou.''
Main use for the \url
command is to specify urls as arguments to
HEVEA commands for hyperlinks (see section 8.1.1) :
\hevea{} home page is
\ahrefurl{\url{http://pauillac.inria.fr/~maranget/hevea/}}
It yields : ``HEVEA home page is
http://pauillac.inria.fr/~maranget/hevea/''.
However the \url
command is fragile, as a consequence it
cannot be used inside \footahref
first argument (This is a
LATEX problem, not an HEVEA one).
The url package solves this problem by providing the
\urldef
command
for defining commands whose body is typeset by using \url
:
\urldef{\heveahome}{\url}{http://pauillac.inria.fr/~maranget/hevea/}
Such a source defines the robust command \heveahome
as the
intended url.
Hence the following source works as expected :
Have a look at \footurl{\heveahome}{\hevea{} home page}
It yields: ``Have a look at HEVEA home page''.
Using \url
inside command definitions with a
#
i argument is a bad idea, since
it gives ``verbatim'' a rather random meaning.
Unfortunately, in some situations (e.g, no %
, no #
),
it may work in LATEX. By
contrast, it does not work in HEVEA. In such situations,
\urldef
should be used.
HEVEA implementation is somehow compatible at the ``programming level''.
Thus, users can define new commands whose argument is understood
verbatim. The urlhref.hva style file
from the distribution
takes advantage of this to define the \url
command, so that it both
typesets an url and inserts a link to it.
\input{urlhref.hva}
Have a look at \url{http://pauillac.inria.fr/~maranget/hevea/}
It yields ``Have a look at http://pauillac.inria.fr/~maranget/hevea/''.
The urlhref.hva
style file (which is an HEVEA style file and not a LATEX
style file) can be adequate for bibliographic references,
which often use \url
for its typesetting power.
Of course, loading urlhref.hva only makes sense when
all arguments to \url
are urls...
B.17.7 |
Verbatim Text : the moreverb and
verbatim Packages |
|
These two packages provide new commands and environments for
processing verbatim text.
I recommend using
moreverb
rather than
verbatim,
since the LATEX implementation of the former
is much more compatible with HEVEA than
the implementation of the latter.