dlvhex

The String Plugin

The String Plugin provides atoms for string operations and manipulations.

&concat takes two strings as input and returns their concatenation:

&concat[A,B](X)
Input:
A
string
B
string
Output:
X
Concatenation of A and B

Example: 

fullstring(Full) :- &concat[P,F](Full), stringpair(P,F).

&strstr evaluates to true if the second input argument is a (case-insensitive) substring of the first:

&strstr[A,B]
Input:
A
string
B
string

Example: 

austrian_phone(P) :- &strstr[P,"+43"], phonenumber(P).

&split splits a string by a specified delimiter:

&split[A,D,N](X)
Input:
A
string to split
D
delimiter
N
index of item to return (starting from 0)
Output:
X
Nth substring of A, split by D

Example: 

month(M) :- &split["2006-04-26","-",1](M).

&sha1sum calculates the SHA1 sum of a string:

&sha1sum[A](X)
Input:
A
string
Output:
X
SHA1 sum of A

Example: 

owner(ID) :- &sha1sum[X](ID), mailbox(X).

$Id: stringplugin.html 2916 2011-05-16 18:33:56Z tkren $

 

Getting Started
HEX-Programs

Description Logic Plugin
RDF Plugin
String Plugin
Merging Plugin

dlvhex Source Documentation
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