is_dma

Checks if a value is a legal Designated Market Area.

Usage

var is_dma=require('is_dma'),
    exceptions=[0],
    value=500;

if(is_dma(value,exceptions)) {
  console.log('%s is a DMA or exception', value);
}

where value is first converted to a string (via .toString()) as are all members of exceptions which is first cloned.

Description

Provides a simple XRegExp-backed function to determine if a provided value is a legal Designated Market Area or contained within a provided list of exceptional values.

The intent of the exceptions array is to allow special values to validate even if they are not DMAs. Many GEO-IP services return '0' for non-matching DMAs so adding that value to exceptions will validate all possible values.

The list of legal DMAs from which this module was constructed were retrieved from DoubleClick's Rich Media API Handbook - Designated Market Area® code key.

NOTE: The term "Designated Market Area" is a registered trademark of DoubleClick.