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# in_chrstore(+CHRConst)

Test if CHRConst is in the CHR constraint store or not

CHRConst
  A CHR constraint

## Description

This predicate is used to test if a particular CHR constraint is in the CHR constraint store or not. It can be used to prevent the addition of redundant constraints. This only useful if the 'already_in_store' option is off.

### Modules

This predicate is sensitive to its module context (tool predicate, see @/2).

## Examples

        X leq Y, Y leq Z ==> \+in_chrstore(X leq Z)| X leq Z.