Records

Different types under one name

• AS topic 10.1 asks you to define a record: one identifier holding fields of different types.
• TYPE … ENDTYPE names the record and declares each field.
• This is not an A2 class. There are no methods here.

TYPE Student
  DECLARE Name : STRING
  DECLARE Mark : INTEGER
ENDTYPE
DECLARE StudentData : Student
StudentData.Name ← "Ada"
StudentData.Mark ← 91
OUTPUT StudentData.Name & " " & NUM_TO_STR(StudentData.Mark)

A field is read with a dot

• StudentData.Name is the Name field of StudentData.
• You may copy a whole record: Pupil2 ← Pupil1 copies every field.
• An array of records uses one index, then the field: Form[1].Mark.

TYPE Student
  DECLARE Name : STRING
  DECLARE Mark : INTEGER
ENDTYPE
DECLARE Form : ARRAY[1:2] OF Student
Form[1].Name ← "Ada"
Form[1].Mark ← 91
Form[2].Name ← "Bo"
Form[2].Mark ← 80
OUTPUT Form[2].Name

Watch out

• Declare the TYPE before you DECLARE a variable of that type.
• Enumerated types and pointers are A2 (topic 13.1). They are not in this AS course.

Common mistakes

• Each field has its own DECLARE inside the TYPE.
• ENDTYPE closes the definition. Forgetting it leaves the type unfinished.

Now you try

• Define a record, store two fields, and output them.

Independent transfer

The final task has no supplied algorithm. Plan its inputs, processing and outputs, then solve it before opening support. Check more than the sample case.