KNX LogicMachine3 Re:actor, Product Manual

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string.gmatch (s, pattern)
Returns an iterator function that, each time it is called, returns the next captures from pattern
over string s. If pattern specifies no captures, then the whole match is produced in each call. As
an example, the following loop
1. s
= "hello world from Lua"
2.
for
w
in string
.gmatch
(
s,
"%a+" ) do
3. print ( w )
4. end
will iterate over all the words from string
s
, printing one per line. The next example collects all
pairs
key=value
from the given string into a table:
1. t
= {}
2. s
= "from=world, to=Lua"
3.
for
k, v
in string
.gmatch
(
s,
"(%w+)=(%w+)" ) do
4. t
[
k
] =
v
5.
end
For this function, a '^' at the start of a pattern does not work as an anchor, as this would prevent
the iteration.
string.gsub (s, pattern, repl [, n])
Returns a copy of s in which all (or the first n, if given) occurrences of the pattern have been
replaced by a replacement string specified by repl, which can be a string, a table, or a function.
gsub also returns, as its second value, the total number of matches that occurred.
If
repl
is a string, then its value is used for replacement. The character % works as an escape
character: any sequence in repl of the form
%n
, with
n
between 1 and 9, stands for the value of
the n-th captured substring (see below). The sequence %0 stands for the whole match. The
sequence %% stands for a single %.
If
repl
is a table, then the table is queried for every match, using the first capture as the key; if
the pattern specifies no captures, then the whole match is used as the key.
If
repl is a function, then this function is called every time a match occurs, with all captured
substrings passed as arguments, in order; if the pattern specifies no captures, then the whole
match is passed as a sole argument.
If the value returned by the table query or by the function call is a string or a number, then it is
used as the replacement string; otherwise, if it is
false
or
nil
, then there is no replacement (that is,
the original match is kept in the string).
Examples:
x
= string.gsub ( "hello world"
,
"(%w+)"
,
"%1 %1" )
--> x="hello hello world world"
x
= string.gsub ( "hello world"
,
"%w+"
,
"%0 %0"
, 1
)
--> x="hello hello world"
x
= string.gsub ( "hello world from Lua"
,
"(%w+)%s*(%w+)"
,
"%2 %1" )
--> x="world hello Lua from"
x
= string.gsub ( "home = $HOME, user = $USER"
,
"%$(%w+)"
,
os.getenv )
--> x="home = /home/roberto, user = roberto"
x
= string.gsub ( "4+5 = $return 4+5$"
,
"%$(.-)%$"
,
function (
s
)
return loadstring (
s
)()
end )
--> x="4+5 = 9"
local
t
= {
name
= "lua"
, version
= "5.1" }