KNX LogicMachine3 Re:actor, Product Manual

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• %x : (where x is any non-alphanumeric character) represents the character x. This is the
standard way to escape the magic characters. Any punctuation character (even the non
magic) can be preceded by a '%' when used to represent itself in a pattern.
•
[set]
: represents the class which is the union of all characters in set. A range of
characters can be specified by separating the end characters of the range with a '-'. All
classes %x described above can also be used as components in set. All other characters in
set represent themselves. For example, [%w_] (or [_%w]) represents all alphanumeric
characters plus the underscore, [0-7] represents the octal digits, and [0-7%l%-] represents
the octal digits plus the lowercase letters plus the '-' character.
• The interaction between ranges and classes is not defined. Therefore, patterns like [%a-
z] or [a-%%] have no meaning.
•
[^set] : represents the complement of set, where set is interpreted as above.
For all classes represented by single letters (%a, %c, etc.), the corresponding uppercase letter
represents the complement of the class. For instance, %S represents all non-space characters.
The definitions of letter, space, and other character groups depend on the current locale. In
particular, the class [a-z] may not be equivalent to %l.
Pattern Item:
A pattern item can be:
• a single character class, which matches any single character in the class;
• a single character class followed by '*', which matches 0 or more repetitions of
characters in the class. These repetition items will always match the longest possible
sequence;
• a single character class followed by '+', which matches 1 or more repetitions of
characters in the class. These repetition items will always match the longest possible
sequence;
• a single character class followed by '-', which also matches 0 or more repetitions of
characters in the class. Unlike '*', these repetition items will always match the shortest
possible sequence;
• a single character class followed by '?', which matches 0 or 1 occurrence of a character
in the class;
• %n, for n between 1 and 9; such item matches a substring equal to the n-th captured
string (see below);
• %bxy, where x and y are two distinct characters; such item matches strings that start
with x, end with y, and where the x and y are balanced. This means that, if one reads the
string from left to right, co1 for an x and -1 for a y, the ending y is the first y
where the count reaches 0. For instance, the item %b() matches expressions with
balanced parentheses.
Pattern:
A pattern is a sequence of pattern items. A '^' at the beginning of a pattern anchors the match at
the beginning of the subject string. A '$' at the end of a pattern anchors the match at the end of
the subject string. At other positions, '^' and '$' have no special meaning and represent
themselves.
Captures:
A pattern can contain sub-patterns enclosed in parentheses; they describe captures. When a
match succeeds, the substrings of the subject string that match captures are stored (captured) for
future use. Captures are numbered according to their left parentheses. For instance, in the pattern
"(a*(.)%w(%s*))", the part of the string matching "a*(.)%w(%s*)" is stored as the first capture