Function findDuplicateOutputs

dash/dash-renderer/src/actions/dependencies.js:357–404

(outputs, head, dispatchError, outStrs, outObjs)

}

function findDuplicateOutputs(outputs, head, dispatchError, outStrs, outObjs) {
    const newOutputStrs = {};
    const newOutputObjs = [];
    outputs.forEach(({id, property}, i) => {
        if (typeof id === 'string') {
            const idProp = combineIdAndProp({id, property});
            if (newOutputStrs[idProp]) {
                dispatchError('Duplicate callback Outputs', [
                    head,
                    `Output ${i} (${idProp}) is already used by this callback.`
                ]);
            } else if (outStrs[idProp]) {
                dispatchError('Duplicate callback outputs', [
                    head,
                    `Output ${i} (${idProp}) is already in use.`,
                    'To resolve this, set `allow_duplicate=True` on',
                    'duplicate outputs, or combine the outputs into',
                    'one callback function, distinguishing the trigger',
                    'by using `dash.callback_context` if necessary.'
                ]);
            } else {
                newOutputStrs[idProp] = 1;
            }
        } else {
            const idObj = {id, property};
            const selfOverlap = wildcardOverlap(idObj, newOutputObjs);
            const otherOverlap = selfOverlap || wildcardOverlap(idObj, outObjs);
            if (selfOverlap || otherOverlap) {
                const idProp = combineIdAndProp(idObj);
                const idProp2 = combineIdAndProp(selfOverlap || otherOverlap);
                dispatchError('Overlapping wildcard callback outputs', [
                    head,
                    `Output ${i} (${idProp})`,
                    `overlaps another output (${idProp2})`,
                    `used in ${selfOverlap ? 'this' : 'a different'} callback.`
                ]);
            } else {
                newOutputObjs.push(idObj);
            }
        }
    });
    keys(newOutputStrs).forEach(k => {
        outStrs[k] = 1;
    });
    newOutputObjs.forEach(idObj => {
        outObjs.push(idObj);
    });
}

function checkInOutOverlap(out, inputs) {
    const {id: outId, property: outProp} = out;