performance improvement in lex_chain, submitted by Markus Triska
performance improvement in lex_chain, submitted by Markus Triska

koryonik/swipl-devel,mndrix/swipl-devel,jn7163/swipl-devel,mndrix/swipl-devel,koryonik/swipl-devel,mndrix/swipl-devel,edechter/swipl-devel,edechter/swipl-devel,jn7163/swipl-devel,jn7163/swipl-devel,mndrix/swipl-devel,jn7163/swipl-devel,koryonik/swipl-devel,koryonik/swipl-devel,koryonik/swipl-devel,edechter/swipl-devel,edechter/swipl-devel,edechter/swipl-devel,mndrix/swipl-devel,jn7163/swipl-devel