leo/docs/rfc/011-scalar-type-accesses-and-methods.md

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# Leo RFC 011: Scalar Type Accesses And Methods
2021-08-14 04:21:39 +03:00
## Authors
The Aleo Team.
2021-08-14 04:21:39 +03:00
## Status
DRAFT
## Summary
This RFC proposes two things:
1. The scalar types in Leo (integers, fields, etc.) can have static methods.
2. The scalar types in Leo (integers, fields, etc.) can have static constants.
3. Those values that have a scalar type can have methods directly on them.
## Motivation
This approach allows for a clean interface to provide built-in methods or static members for these basic types.
## Design
### Semantics
Firstly we would have to modify both the ABNF and parsing of Leo to allow static method calls onto a scalar type.
The ABNF would look as follows:
```abnf
; This is an existing old rule
scalar-type = boolean-type / arithmetic-type / address-type / character-type
; This is an existing old rule
circuit-type = identifier / self-type
; Add this rule.
named-type = circuit-type / scalar-type ; new rule
; Modify this rule:
postfix-expression = primary-expression
/ postfix-expression "." natural
/ postfix-expression "." identifier
/ identifier function-arguments
/ postfix-expression "." identifier function-arguments
/ named-type "::" identifier function-arguments ; this used to be a circuit-type
/ named-type "::" identifier ; this is new to allow static members on
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/ postfix-expression "[" expression "]"
/ postfix-expression "[" [expression] ".." [expression] "]"
```
Now methods and static members would be first-class citizens of scalar types and their values. For example, the following could be done:
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```ts
let x = 1u8.to_bits(); // A method call on on a scalar value itself
let x = u8::MAX; // A constant value on the scalar type
let y = u8::to_bits(1u8); // A static method on the scalar type
```
## Drawbacks
This change adds more complexity to the language.
## Effect on Ecosystem
None. The new parsing changes would not break any older programs.
## Alternatives
None.