tricu

An interpreted language for exploring Tree Calculus
Log | Files | Refs | README | LICENSE

registration.tri (1759B)

      1 !import bd2c14d6db6b69308a5252a8e839705a55d30e815f012900b094315263e08d81 *
      2 !import 3f70d95cf1bae0928ee89acd2a9e0cdd8287796efae32a9f08d33e3dd0149c55 as A
      3 !export main
      4 
      5 -- Registration validator: name, email, age, termsAccepted are separate arguments.
      6 -- Returns one field-specific message per input, plus an accepted Boolean.
      7 -- Name must be nonempty scalar text. Age must be a natural from 18 to 120.
      8 -- Email uses a deliberately small rule: nonempty text containing @ and a dot.
      9 -- Terms must be the canonical true Boolean. This is a teaching policy, not SMTP validation.
     10 -- Browser and server can pin this same executable instead of duplicating rules.
     11 -- Records use [fieldName tag value]: 0 = text, 1 = natural, 2 = Boolean.
     12 -- Base supplies arithmetic/Booleans; A.hostString? checks Unicode scalar text.
     13 
     14 nameMessage name = case A.hostString? name of
     15   ^true = (case name of
     16     [] = "Name is required."
     17     _ = "")
     18   _ = "Name must be scalar text."
     19 
     20 emailMessage email = case A.hostString? email of
     21   ^true = (case and? (contains? "@" email) (contains? "." email) of
     22     ^true = ""
     23     _ = "Email must contain @ and a dot.")
     24   _ = "Email must be scalar text."
     25 
     26 ageMessage age = case isNat? age of
     27   ^true = (case and? (lte_? 18 age) (lte_? age 120) of
     28     ^true = ""
     29     _ = "Age must be from 18 to 120.")
     30   _ = "Age must be a canonical natural."
     31 
     32 termsMessage ^true = ""
     33 termsMessage _ = "Accept the terms."
     34 
     35 report name email age terms = [
     36   ["accepted" 2 (and? (equal? name "") (and? (equal? email "") (and? (equal? age "") (equal? terms ""))))]
     37   ["nameError" 0 name] ["emailError" 0 email]
     38   ["ageError" 0 age] ["termsError" 0 terms]]
     39 
     40 main name email age terms = report (nameMessage name) (emailMessage email) (ageMessage age) (termsMessage terms)