Difference between revisions of "LlLinksetDataFindKeys"

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The '''llLinksetDataFindKeys''' function returns a list of up to {{LSLP|count}} keys from the datastore that match {{LSLP|pattern}}, starting at the one indicated by {{LSLP|start}}. If {{LSLP|count}} is less than 1, then all keys between {{LSLP|start}} and the end which match {{LSLP|pattern}} are returned.  
The '''llLinksetDataFindKeys''' function returns a list of up to {{LSLP|count}} keys from the datastore that match {{LSLP|pattern}}, starting at the one indicated by {{LSLP|start}}. If {{LSLP|count}} is less than 1, then all keys between {{LSLP|start}} and the end which match {{LSLP|pattern}} are returned. If {{LSLP|count}} minus {{LSLP|start}} exceeds the number of matching keys, the returned list will be shorter than {{LSLP|count}}, down to a zero-length list if {{LSLP|start}} equals or exceeds the number of matching keys.
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{{LSLP|pattern}} is a [https://en.wikipedia.org/wiki/Regular_expression Regular expression].
{{LSLP|pattern}} is a [https://en.wikipedia.org/wiki/Regular_expression Regular expression].


|caveats
|caveats=
* Unlike [[llLinksetDataListKeys]], the order of the returned list is neither usefully sorted nor predictable.
** The order of keys returned is the same through successive calls, even if {{LSLP|pattern}} has changed. However, when a new key-value pair is added, it is added essentially randomly in the order. Additionally, while writing the same sequence of key-value pairs after successive calls to [[llLinksetDataReset]], or in different linksets, occasionally results in the same ordering, this behavior is by no means guaranteed.
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Revision as of 21:39, 14 January 2023

Summary

Function: list llLinksetDataFindKeys( string pattern, integer start, integer count );
0.0 Forced Delay
10.0 Energy

The llLinksetDataFindKeys function returns a list of up to count keys from the datastore that match pattern, starting at the one indicated by start. If count is less than 1, then all keys between start and the end which match pattern are returned. If count minus start exceeds the number of matching keys, the returned list will be shorter than count, down to a zero-length list if start equals or exceeds the number of matching keys.
Returns a list of the keys in the datastore.

• string pattern A regular expression describing which keys to return.
• integer start The first key to return.
• integer count The number of keys to return.

Specification

pattern is a Regular expression.

Caveats

  • Unlike llLinksetDataListKeys, the order of the returned list is neither usefully sorted nor predictable.
    • The order of keys returned is the same through successive calls, even if pattern has changed. However, when a new key-value pair is added, it is added essentially randomly in the order. Additionally, while writing the same sequence of key-value pairs after successive calls to llLinksetDataReset, or in different linksets, occasionally results in the same ordering, this behavior is by no means guaranteed.

Examples

Notes

Regular Expression Cheat Sheet

Wildcard
. Matches any character
Anchors
^ Matches the beginning of the string.
$ Matches the end of the string.
Expression Prefixes
(?i) Makes search string case insensitive. This must be the first thing that appears in the search string.

"(?i)apple" will match "apple", "APPLE", "ApPlE", and any other combination of upper and lower case characters.

$ Matches the end of the string.
Repeats
* Matches the preceding atom 0 or more times.
+ Matches the preceding atom 1 or more times.
? Matches the preceding atom 0 or 1 times.
{n}

{n,}

{n, m}

Matches the preceding atom n, n or more, or between n and m times.
Sub-expressions
(expression) Text enclosed in parentheses is a marked sub-expression. Text matched as part of a sub-expressions is split out and may be repeated.
Alternation
a | b Match either a or b.
Character Sets
[abc] Matches any one of the enumerated characters.
[a-c] Matches any character in the specified range.
[^abc] Matches any character other than the enumerated characters.
[[:name:]] Matches any character of the named class.
Any of the above character set definitions may be combined.
Escape Sequences
Specific Characters
\e ASCII 0x1B, ESC
\n New line
\r Carriage return
\t Tab
\xdd Matches an ASCII character with the code dd
Single character classes
\d

\D

Any decimal digit.
  • \d → [[:digit:]] or [0-9]
  • \D → [^[:digit:]] or [^0-9]
\l

\L

Any lower case character.
  • \l → [[:lower:]] or [a-z]
  • \L → [^[:lower:]] or [^a-z]
\s

\S

Any whitespace character.
  • \s → [[:space:]] or [ \t\r\n]
  • \S → [^[:space:]] or [^ \t\r\n]
\u

\U

Any upper case character.
  • \u → [[:upper:]] or [A-Z]
  • \U → [^[:upper:]] or [^A-Z]
\w

\W

Any "word" character.

Alphanumeric plus underscore

  • \w → [[:upper:][:lower:][:digit:]_] or [A-Za-z0-9_]
  • \W → [^[:upper:][:lower:][:digit:]_] or [^A-Za-z0-9_]
Word boundaries
\< Start of word.
\> End of word
\b
\B Not a word boundary.

*Note* LSL uses '\' as an escape character in strings. The escape characters above must be double escaped. So "\d" needs to be written in LSL as "\\d"

Please see LSL Strings, Escape Codes

Named Character Classes
alnum Any alpha-numeric character.
  • [[:alnum:]] → [0-9a-zA-Z]
  • [^[:alnum:]] → [^0-9a-zA-Z]
alpha Any alphabetic character.
  • [[:alpha:]] → [a-zA-Z]
  • [^[:alpha:]] → [^a-zA-Z]
blank Any whitespace character that is not a line separator.
cntrl Any control character
  • [[:cntrl:]] → [\x01-\x31]
  • [^[:cntrl:]] → [^\x01-\x31]
digit

d

Any decimal digit
  • [[:digit:]] → [0-9]
  • [^[:digit:]] → [^0-9]
lower

l

Any lower case character.
  • [[:lower:]] → [a-z]
  • [^[:lower:]] → [^a-z]
print Any printable character.
punct Any punctiation character.
space

s

Any whitespace character.
upper

u

Any upper case character.
  • [[:upper:]] → [A-Z]
  • [^[:upper:]] → [^A-Z]
word

w

Any control character
  • [[:word:]] → [0-9a-zA-Z_]
  • [^[:word:]] → [^0-9a-zA-Z_]
xdigit Any hexadecimal digit character
  • [[:xdigit:]] → [0-9a-fA-F]
  • [^[:xdigit:]] → [^0-9a-fA-F]

Deep Notes

Signature

function list llLinksetDataFindKeys( string pattern, integer start, integer count );