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Merge a big batch of documentation fixes for escaping, marking URLs, places

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where verbatim text went off the end of the page on the PDF, and various
other improvements
(closes issue #10307, IgorG)


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@77284 65c4cc65-6c06-0410-ace0-fbb531ad65f3
This commit is contained in:
Russell Bryant
2007-07-26 14:49:51 +00:00
parent 70f140c1d2
commit 51e7035dfe
18 changed files with 205 additions and 137 deletions
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142
doc/tex/channelvariables.tex
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@@ -170,10 +170,10 @@ The double quotes will be counted as part of that lexical token.
As an example:
\begin{verbatim}
exten => s,6,GotoIf($[ "${CALLERIDNAME}" : "Privacy Manager" ]?callerid-liar|s|1:s|7)
exten => s,6,GotoIf($[ "${CALLERID(name)}" : "Privacy Manager" ]?callerid-liar|s|1:s|7)
\end{verbatim}
The variable CALLERIDNAME could evaluate to "DELOREAN MOTORS" (with a space)
The variable CALLERID(name) could evaluate to "DELOREAN MOTORS" (with a space)
but the above will evaluate to:
\begin{verbatim}
@@ -197,67 +197,77 @@ evaluate this expression, because it does not match its grammar.
Operators are listed below in order of increasing precedence. Operators
with equal precedence are grouped within { } symbols.
\begin{verbatim}
expr1 | expr2
Return the evaluation of expr1 if it is neither an empty string
nor zero; otherwise, returns the evaluation of expr2.
\begin{itemize}
\item \verb!expr1 | expr2!
expr1 & expr2
Return the evaluation of expr1 if neither expression evaluates to
an empty string or zero; otherwise, returns zero.
Return the evaluation of expr1 if it is neither an empty string
nor zero; otherwise, returns the evaluation of expr2.
expr1 {=, >, >=, <, <=, !=} expr2
Return the results of floating point comparison if both arguments are
numbers; otherwise, returns the results of string comparison
using the locale-specific collation sequence. The result of each
comparison is 1 if the specified relation is true, or 0 if the
relation is false.
\item \verb!expr1 & expr2!
expr1 {+, -} expr2
Return the results of addition or subtraction of floating point-valued
arguments.
Return the evaluation of expr1 if neither expression evaluates to
an empty string or zero; otherwise, returns zero.
expr1 {*, /, %} expr2
Return the results of multiplication, floating point division, or
remainder of arguments.
\item \verb+expr1 {=, >, >=, <, <=, !=} expr2+
- expr1
Return the result of subtracting expr1 from 0.
This, the unary minus operator, is right associative, and
has the same precedence as the ! operator.
Return the results of floating point comparison if both arguments are
numbers; otherwise, returns the results of string comparison
using the locale-specific collation sequence. The result of each
comparison is 1 if the specified relation is true, or 0 if the
relation is false.
! expr1
Return the result of a logical complement of expr1.
In other words, if expr1 is null, 0, an empty string,
or the string "0", return a 1. Otherwise, return a 0.
It has the same precedence as the unary minus operator, and
is also right associative.
\item \verb!expr1 {+, -} expr2!
expr1 : expr2
The `:' operator matches expr1 against expr2, which must be a
regular expression. The regular expression is anchored to the
beginning of the string with an implicit `^'.
Return the results of addition or subtraction of floating point-valued
arguments.
If the match succeeds and the pattern contains at least one regu-
lar expression subexpression `\(...\)', the string correspond-
ing to `\1' is returned; otherwise the matching operator
returns the number of characters matched. If the match fails and
the pattern contains a regular expression subexpression the null
string is returned; otherwise 0.
\item \verb!expr1 {*, /, %} expr2!
Normally, the double quotes wrapping a string are left as part
of the string. This is disastrous to the : operator. Therefore,
before the regex match is made, beginning and ending double quote
characters are stripped from both the pattern and the string.
Return the results of multiplication, floating point division, or
remainder of arguments.
expr1 =~ expr2
Exactly the same as the ':' operator, except that the match is
not anchored to the beginning of the string. Pardon any similarity
to seemingly similar operators in other programming languages!
The ":" and "=~" operators share the same precedence.
\item \verb!- expr1!
expr1 ? expr2 :: expr3
Traditional Conditional operator. If expr1 is a number
Return the result of subtracting expr1 from 0.
This, the unary minus operator, is right associative, and
has the same precedence as the ! operator.
\item \verb+! expr1+
Return the result of a logical complement of expr1.
In other words, if expr1 is null, 0, an empty string,
or the string "0", return a 1. Otherwise, return a 0.
It has the same precedence as the unary minus operator, and
is also right associative.
\item \verb!expr1 : expr2!
The `:' operator matches expr1 against expr2, which must be a
regular expression. The regular expression is anchored to the
beginning of the string with an implicit `\^'.
If the match succeeds and the pattern contains at least one regular
expression subexpression `\(...\)', the string corresponing
to `\textbackslash1' is returned; otherwise the matching operator
returns the number of characters matched. If the match fails and
the pattern contains a regular expression subexpression the null
string is returned; otherwise 0.
Normally, the double quotes wrapping a string are left as part
of the string. This is disastrous to the : operator. Therefore,
before the regex match is made, beginning and ending double quote
characters are stripped from both the pattern and the string.
\item \verb!expr1 =~ expr2!
Exactly the same as the ':' operator, except that the match is
not anchored to the beginning of the string. Pardon any similarity
to seemingly similar operators in other programming languages!
The ":" and "=\~" operators share the same precedence.
\item \verb!expr1 ? expr2 :: expr3!
Traditional Conditional operator. If expr1 is a number
that evaluates to 0 (false), expr3 is result of the this
expression evaluation. Otherwise, expr2 is the result.
If expr1 is a string, and evaluates to an empty string,
@@ -267,7 +277,7 @@ with equal precedence are grouped within { } symbols.
will be the result of the "evaluation" of this
expression. expr3 will be the result otherwise. This
operator has the lowest precedence.
\end{verbatim}
\end{itemize}
Parentheses are used for grouping in the usual manner.
@@ -276,7 +286,7 @@ or C derived languages.
\subsection{Floating Point Numbers}
In 1.6 and above, we shifted the \$\[...\] expressions to be calculated
In 1.6 and above, we shifted the \$[...] expressions to be calculated
via floating point numbers instead of integers. We use 'long double' numbers
when possible, which provide around 16 digits of precision with 12 byte numbers.
@@ -309,7 +319,7 @@ don't want to preclude it, either.
Here is a list of the 'builtin' functions in Expr2. All other dialplan functions
are available by simply calling them (read-only). In other words, you don't need to
surround function calls in \$\[...\] expressions with \$\{...\}. Don't jump to conclusions,
surround function calls in \$[...] expressions with \$\{...\}. Don't jump to conclusions,
though! -- you still need to wrap variable names in curly braces!
\begin{enumerate}
@@ -338,6 +348,7 @@ If this quotient is 1/2, it is rounded to the nearest even number.
\subsection{Examples}
\begin{astlisting}
\begin{verbatim}
"One Thousand Five Hundred" =~ "(T[^ ]+)"
returns: Thousand
@@ -422,10 +433,11 @@ TRUNC(-3.5)
returns -3.
\end{verbatim}
\end{astlisting}
Of course, all of the above examples use constants, but would work the
same if any of the numeric or string constants were replaced with a
variable reference \${CALLERIDNUM}, for instance.
variable reference \${CALLERID(num)}, for instance.
\subsection{Numbers Vs. Strings}
@@ -453,7 +465,7 @@ This is designed to be used together with the expression syntax described
above, eg :
\begin{verbatim}
exten => 1,2,GotoIf($[${CALLERID} = 123456]?2|1:3|1)
exten => 1,2,GotoIf($[${CALLERID(all)} = 123456]?2|1:3|1)
\end{verbatim}
Example of use :
@@ -472,7 +484,7 @@ Syntax errors are now output with 3 lines.
If the extensions.conf file contains a line like:
\begin{verbatim}
exten => s,6,GotoIf($[ "${CALLERIDNUM}" = "3071234567" & & "${CALLERIDNAME}" : "Privacy Manager" ]?callerid-liar|s|1:s|7)
exten => s,6,GotoIf($[ "${CALLERID(num)}" = "3071234567" & & "${CALLERID(name)}" : "Privacy Manager" ]?callerid-liar|s|1:s|7)
\end{verbatim}
You may see an error in /var/log/asterisk/messages like this:
@@ -635,7 +647,7 @@ references with '555'. You can override the 555 for variable values,
by entering in var=val arguments after the filename on the command
line. So...
check\_expr /etc/asterisk/extensions.conf CALLERIDNUM=3075551212 DIALSTATUS=TORTURE EXTEN=121
check\_expr /etc/asterisk/extensions.conf CALLERID(num)=3075551212 DIALSTATUS=TORTURE EXTEN=121
will substitute any \${CALLERIDNUM} variable references with
3075551212, any \${DIALSTATUS} variable references with 'TORTURE', and
@@ -644,15 +656,19 @@ going on in the reference, like \${EXTEN:2}, then the override will
not work. Everything in the \${...} has to match. So, to substitute
\${EXTEN:2} references, you'd best say:
check\_expr /etc/asterisk/extensions.conf CALLERIDNUM=3075551212 DIALSTATUS=TORTURE EXTEN:2=121
check\_expr /etc/asterisk/extensions.conf CALLERID(num)=3075551212 DIALSTATUS=TORTURE EXTEN:2=121
on stdout, you will see something like:
OK -- \$[ "\${DIALSTATUS}" = "TORTURE" | "\${DIALSTATUS}" = "DONTCALL" ] at line 416
\begin{verbatim}
OK -- $[ "${DIALSTATUS}" = "TORTURE" | "${DIALSTATUS}" = "DONTCALL" ] at line 416
\end{verbatim}
In the expr2\_log file that is generated, you will see:
line 416, evaluation of \$[ "TORTURE" = "TORTURE" | "TORTURE" = "DONTCALL" ] result: 1
\begin{verbatim}
line 416, evaluation of $[ "TORTURE" = "TORTURE" | "TORTURE" = "DONTCALL" ] result: 1
\end{verbatim}
check\_expr is a very simplistic algorithm, and it is far from being
guaranteed to work in all cases, but it is hoped that it will be
@@ -712,7 +728,7 @@ ${SYSTEMNAME} * value of the systemname option of asterisk.conf
\end{verbatim}
\subsection{Application return values}
-------------------------
In Asterisk 1.2, many applications return the result in a variable
instead of, as in Asterisk 1.0, changing the dial plan priority (+101).
For the various status values, see each application's help text.