Values and Types in Ballerina

Ballerina programs operate on a rich universe of values. This universe of values is partitioned into a number of basic types; every value belongs to exactly one basic type.

A variable has a type, which constrains what values the variable can hold.

Values are of four kinds, each corresponding to a kind of basic type:

1. Simple values - which are not constructed from other values;
   • nil, boolean, int, float, decimal
2. Structured values - which contain other values. They are containers for other values, which are called their members.
   • array, map, record, table, tuple
3. Sequence values - which consists of an ordered sequence of zero or more constituent items, where the constituent items belong to the same basic type as the sequence value itself.
   • string, xml
4. Behavioral values- which are not just data
   • function, object, error, stream, future, typedesc
5. Other - which allows some flexibility to define custom types based on the combination of two or more types.
   • any, anydata, json, byte and union

Let's learn the Ballerina types in detail.

• Simple Basic Types

  • Integer
  • Float
  • Decimal
  • Boolean
  • Nil

• Sequence Types

  • String
    • String Template Literal
  • XML

• Structured Types

  • Lists
    • Array
    • Tuple
  • Mappings
    • Map
    • Record
  • Table

• Behavioral Types

  • object
  • stream
  • error
  • typedesc
  • function
  • future

• Other Types

  • any
  • anydata
  • byte
  • json
  • union