better type checking for +/1 and */1
better type checking for +/1 and */1

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