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Ignoring the fact condition when the fact is not passed in

See original GitHub issue


I would have liked the rule engine to ignore the fact condition if it is in “ANY” when the fact is not passed in, e.g.,

If my facts are these:

let facts = {
    gameDuration: 40

And my rule is:

    conditions: {
      any: [{
        fact: 'personalFoulCount',
        operator: 'greaterThanInclusive',
        value: 5
          fact: 'gameDuration',
          operator: 'equal',
          value: 40
    event: {  // define the event to fire when the conditions evaluate truthy
      type: 'fouledOut',
      params: {
        message: 'Player has fouled out!'

I would have preferred the rule engine would not have errored out and ignore the fact that personalFoulCount is not there as it was in ANY condition clause.

Issue Analytics

  • State:closed
  • Created 7 years ago
  • Comments:10 (5 by maintainers)

github_iconTop GitHub Comments

CacheControlcommented, Jan 23, 2017

@arsalans this feature is now available in 1.4.0 as an allowUndefinedFacts engine option. Please see the updated docs

CacheControlcommented, Jan 20, 2017

@arsalans yep, we’re aligned. Any unregistered fact will simply be treated as a falsey condition. This could mean a rule still evaluates truthy, as in the ANY scenario you mentioned. I’ll attempt to come up with a better term than ignoreUnregisteredFacts that better explains the behavior

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