TeX likes the \ symbol. In a mathematical text, the probability that alpha means the corresponding Greek letter is above 99.99 percent. It is almost inconceivable that the author wanted to use this sequence of five letters. Why must then we use "\alpha"?
Accents are frequently used in mathematical text. Among them the prime is denoted in the natural order as "a'", while one cannot say "a bar" or "a dot". Instead the accent is indicated by a word before the letter as in "\tilde a".
The texpp TeX Preprocessor makes it easier to produce, and helps to understand at a glimpse by allowing arbitrary character sequences as macro names. The preprocessor reads several files, understands and evaluates macro definitions, and later the invocations are replaced by the body of the macro. The process results in a single file. Using the features in the preprocessor, the problems indicated above, as well as several others, can be solved. Naturally there remain several drawbacks inherent in TeX language.
\/ |-- /\ ...
<= <: x1 M
Macro names are recongized only if they are separated from their environment
by a space (tab, newline) characters, or by one of the grouping {,
} characters. Thus a name can be a proper subset of another name
with no problem, as "..." and "...,".
%define <parameters> macroname <parameters> %text% comment
%mdefine <parameters> macroname <parameters> %text% comment
The two forms tell when should the macro name be substituted. In the first
case the name is always replaced by the macro body, while in the second case
only in math and display mode, that is, between $ or $$ signs
but see section 5. A single name might have only one type of definition at
the same time.
If the definition does not fit into a single line, the macro text can be continued. In this case the line should end with a \ character which is left out from the macro text.
In the definition parameters are denoted by "#1" up to "#9". Thus if the # sign occurs either in the macro name or in the macro text, it should be doubled. Before the macro name, and between the macro name and the % mark denoting the start of the macro body, only parameter denotations might occur. The macro text is closed also by a percentage % mark, everything after it until the end of the line is comment, and left out. The macro body defines the replacement text, in it parameter denotations might occur anywhere and in any number; they will be replaced by the value of the parameters at the invocation.
The macro body might contain other macro names defined earlier; they are substituted when the definition is elaborated. Thus macro definitions are static, not dynamic.
Macro names can be redefined. In these cases the earlier definition is not lost, but become hidden. Any macro definition can be revoked by issuing the command
%undefine macroname % commentstarting at the beginning of a line. The last definition of the macro is dropped, and the previous definition (if any) is restored. This feature can be used to define temporary macros without risking to lost any earlier definition.
%mathmode <entering sequence> <leaving sequence>
%dispmode <entering sequence> <leaving sequence>
Here "entering sequence" is the (macro) name which is used to switch
to the appropriate mode, "leaving sequence" which denotes the end of
the mode. These names must occur in pairs, and cannot interleave. If both
sequences are the same, it is not necessary to duplicate it. It could be
useful to use different sequences to denote the beginning and the end of a
formula display; this could prevent TeX misinterpreting your text if you
left out a closing $$ sequence. The preprocessor tells you if modes
are not properly embedded. The following definitions are especially handy
when using LaTeX:
%mathmode \( \) % for plain math mode
%mathmode \math \endmath
%dispmode \[ \] % for displayed formulas
%dispmode \equation \endequation
%indentspaces <entering sequence> <leaving sequence>Here, as before, if both sequences are the same, it is enough to give only the first one.
\preserve <anything_which_does_not_have_spaces_and_opening_brace>
\preserve {text in which curly brackets are balanced}
In the argument of "\preserve" there is no macro replacement; the
macro name won't appear in the final text. In a macro definition the
"\preserve" cannot be applied to the parameters, as expansion of
parameters happens before consulting the macro text.
Special parameter handling can be instructed by the following directives:
%preservepar <macroname>
%plainpar <macroname>
%mathpar <macroname>
The macroname appearing in any of these directives must be defined,
cannot have any left parameters, and must have at least one right parameter.
All right parameters of the macro are handled according to the directive. In
the first case the parameters is taken as is (no further macro substitution
is made). In the second case the parameter is evaluated in plain (not math)
mode, independently of the present mode; while in the last case the
parameter is evaluated in math mode. It is an error (and meaningless anyway)
to use the "%mathpar" directive for a macro defined with
"%mdefine".
These possibilities are handy for the array environment in LaTeX:
%mdefine btab #1 %\begin{array}{#1}%
%mdefine etab %\end{array}%
%preservepar btab
The only argument of the btab macro is a sequence of letters
l, c, and r which defines how many columns the
array has and how its fields should be aligned. Naturally, this parameter
should left alone.
%mdefine \hbox #1 %\hbox{#1}%
%plainpar \hbox
Very frequently a box also gets its size, as is the case in "\hbox to
1.5cm {...}". Seeing this construct, the preprocessor would take
"to" as the argument for \hbox. To mend the situation, the
preprocessor knows the following definitions, too:
%define <macroname> #1 {#2} %replacement text % comment
%mdefine <macroname> #1 {#2} %replacement text % comment
The macro must have exactly two right parameters, the second one is enclosed
into curly brackets. When invoking the macro definition, the second
parameter must be inside curly brackets, everything between the macro name
and the opening curly bracket will be the value of the first parameters. The
first parameter can be empty. Using this, the definition of the boxes goes
as follows:
%mdefine \hbox #1{#2} %\hbox #1{#2}%
%plainpar \hbox
%mdefine \vbox #1{#2} %\vbox #1{#2}%
%plainpar \vbox
There is a possibility to give the character by its code. In this case its code in decimal should be given after a \. (Of course, to define a single \ as a character to be replaced, the \\ pair should be given.) For example, the letter "í" has code 237 (say), both of the next two lines work well
í "{\'\i}"
\237 "\'\i "
%define #1 *2 %#1#1% temporary, for doubling
%define #1 *8 %#1 *2 *2 *2% apply *2 three times
%undefine *2 % not needed any more
Parameters are assigned from left to right, thus the third "*2" has
its argument as the result of the replacement in "#1 *2 *2", that
is "#1#1#1#1". Consequently the body of the "*8" macro
will be "#1#1#1#1#1#1#1#1" as required. Using this, the result of
both "x 1 *8 y" and "x{1}*8 y" will be
"x11111111y". (Observe that the space after "*8" has
vanished.) However, "x 1*8 y" and "x 1 *8y" remain
unchanged as the macro name "*8" cannot be extracted. As another
example, in "x {a b} *8 y" the space between a and
b as well as the space before the opening brace survives in the
replacement, but the space after the macro name vanishes. The result will be
"x a ba ba ba ba ba ba ba by".
%define [[ %[% now [[ is replace by a single [
%define ]] %]% similarly for ]]
%define [ %\{% from now on [ means \{
%define ] %\}% and ] means \}
These definitions can be used to transform the formula of the first line
into the formula of the second line:
a = [ 0, 1, 2, ..., n ] + [ 2n, ..., 4n ]
a =\{0, 1, ..., n\}+\{2n, ..., 4n\}
while a reference which must go between square brackets can be enclosed by
double brackets, as from "[[ a ]]" will produce "[a]".
Exchanging the first two lines and last two lines in the above definition
yields identical replacements for both "[[" and "[", i.e.
"\{".
%mdefine /\ %\wedge % "and" symbol
%mdefine \/ %\vee % "or" symbol
%mdefine |-- %\vdash % derivable
%mdefine |== %\models % semantically follows
%mdefine --> %\rightarrow % implies
%mdefine phi %\varphi %
%mdefine ALL %\forall %
%mdefine not %\neg % negation symbol
%mdefine ... %\ldots % ellipsis
As the preprocessor does not handle \ specially, both /\
and \/ are recognised with no problem. The spaces at the end of the
macro definitions are needed as the replacing mechanism erases spaces
following the macro name. Without these spaces the TeX commands would merge
with the following symbols. Using these definitions we can write
$$ |== ALL x ( phi (x) \/ not phi (x) ) $$
$$ |-- phi --> ( not phi --> phi )$$
while the official TeX forms are
$$\models\forall x (\varphi(x)\vee\neg\varphi(x) ) $$
$$\vdash\varphi\rightarrow(\neg\varphi\rightarrow\varphi)$$
$e^{x^{2}/2 } ) = (e^{x^{2}/2} )$
(watch for the spaces). In the definition curly brackets around
#2 are necessary as we want the whole second argument be in the
exponent. Without these brackets the expanded form of the left hand side
would be "(e^x^2/ 2 )", definitely not what was wanted.
\def\mydispformula#1#2{#2\leqno #1} %TeX definition
%dispmode .EQ .EN
%define .EQ #1 %$$\mydispformula{#1}{% call TeX macro
%define .EN %}$$%
Using these we could write
.EQ (1)
a=b+c
.EN
As the macroname has a right parameter, even if the formula has no number
at all, we still must supply the parameter. For this purpose the
empty argument "{}" can be used as ".EQ {}". Not
doing so, the first symbol in the formula is used as the number.
| -h | help | ||
| -s | silent: do not write messages | ||
| -t xxxx | use xxxx as translation file | ||
| -m xxxx | read macro file xxxx, don't produce output | ||
| -w xxxx | write the result to file xxxx | ||
| -a xxxx | append result to file xxxx | ||
| -w- | do not give output, check only |
Using the -w switch, the given file, if exists, is erased first. With -a the new material is added at the end. If neither -a nor -w appears, the result goes to the standard output.
All the files on the argument list are processed in the order they are given, a single - indicates reading from stdin.
The environment variable TEXPP is checked first for switches and file names, its content should be similar to an argument list. Switches given after the command name have priority over the ones in the environment variable; file names there are processed before the files appearing in the argument.
Error messages are printed to the standard error, and also appear in the output marked by "%%%TeXpp Error". The program exits with value 0 if no errors were encountered, otherwise it exits with value 1.