Regular Expression Operators

Regular expression operators:

~   complement
\   term complement
&   intersection
-   minus

$.  contains once
$?  contains optionally
$   contains once or more
( ) optionality

+   Kleene plus
*   Kleene star

./. ignore internally (not yet implemented)
/   ignoring

|   union

<>  shuffle
<   before
>   after

.o.   composition
.O.   lenient composition
.m>.  merge right
.<m.  merge left
.x.   cross product
.P.   input priority union
.p.   output priority union
.-u.  input minus
.-l.  output minus
`[ ]  substitute

^n,k  catenate from n to k times, inclusive
^>n   catenate more than n times
^>n   catenate less than n times
^n    catenate n times

.r   reverse
.i   invert
.u   input side
.l   output side

\\\  left quotient
Two-level rules:

 \<=   left restriction
 <=>   left and right arrow
 <=    left arrow
 =>    right arrow

Replace rules:

 ->    replace right
 (->)  optionally replace right
 <-    replace left
 (<-)  optionally replace left
 <->   replace left and right
 (<->) optionally replace left and right
 @->   left-to-right longest match
 @>    left-to-right shortest match
 ->@   right-to-left longest match
 >@    right-to-left shortest match

Rule contexts, markers and separators:

 ||   match contexts on input sides
 //   match left context on output side and right context on input side
 \   match left context on input side and right context on output side
 \/   match contexts on output sides
 _    center marker
 ...  markup marker
 ,,   rule separator in parallel rules
 ,    context separator
 [. .]  match epsilons only once

Read from file:

 @bin" "  read binary transducer
 @txt" "  read transducer in att text format
 @stxt" " read spaced text
 @pl" "   read transducer in prolog text format
 @re" "   read regular expression

Symbols:

 .#.  word boundary symbol in replacements, restrictions
 0    the epsilon
 ?    any token
 %    escape character
 { }  concatenate symbols
 " "  quote symbol

:    pair separator
::   weight

;   end of expression
!   starts a comment until end of line
#   starts a comment until end of line

Also see more information on special symbols.