syntax.md

Syntax design

Why is the syntax the way it is?

No Block Comments

Bait does not support block comments:

• Complicates lexing and parsing, especially nested block comments
• Hard to format, especially inline comments (a built-in formatter is planned)

Using a decent editor with line wrapping and shortcuts, you can achieve almost the same level of convenience!

For details, I recommend reading https://futhark-lang.org/blog/2017-10-10-block-comments-are-a-bad-idea.html.

Casting: val as Type

Benefits

• Natural logic flow
  • Flow from left to right, mirroring natural language
  • Consistent with general design "value before type", e.g. function parameters
• No ambiguity: Use of the designated keyword as
• Efficient parsing

Alternatives considered

• Type(val)
  • Confusable with function calls: Type(val) vs func(param)
  • Problematic parsing without unlimited lookahead, e.g.
    • References &u8
    • (nested) Arrays [][]f64
  • Harder to type as code has to be inserted before and after the casted value

References

• Discord: Thoughts by @zeozeozeo
• soc.me: ident: Type over Type ident

Static Variables

Benefits

• No name collision with symbols in other packages
• Clear scope and explicit usage

Alternatives considered

• Global variables
  • Hard to trace where a variable and value changes come from
  • Unintended coupling of independent code parts

References

• GH-249 by @StunxFS

Function Types

Parameter names of function types must be named, e.g.

type Fetch := fun (method string, url string) []u8

Benefits

• Improved Readability:
  • Purpose of each argument is easier to understand
  • Reduced chance of parameter mix-ups
• Better tooling support and documentation

Alternatives considered

• type Fetch := fun (string, string) []u8