FIXED: Position logic for DCGs that produce no body.
FIXED: Position logic for DCGs that produce no body.

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