validFrom constant
validFrom [Expects: https://schema.org/Date, https://schema.org/DateTime]
The date when the item becomes valid.
Can be used on: https://schema.org/Certification, https://schema.org/Demand, https://schema.org/FinancialIncentive, https://schema.org/LocationFeatureSpecification, https://schema.org/MonetaryAmount, https://schema.org/Offer, https://schema.org/OpeningHoursSpecification, https://schema.org/Permit, https://schema.org/PriceSpecification
Implementation
static const validFrom = IriTerm.prevalidated('https://schema.org/validFrom');