Global Conditions

isNull(var)

return true if var is a null type, false otherwise

isNull("Hello") // return false  
isNull(null) // return true

isUndef(var)

return true if var is undefined type, false otherwise

isUndef(null) // return false

let s = coalesce("", "", "") // return undefined  
isUndef(s) // return true

isString(var)

return true if var is of string type, false otherwise

isString("abc") // return true  
isString(64) // return false

isBlob(var)

return true if var is of blob type, false otherwise

isNumber(var)

return false if var is of int64 or float64 type, false otherwise

isNumber("abc") // return false  
isNumber(64) // return true