Grammar

The full EBNF will live in compiler/README.md. This is the shape:

file       = needs { statement }
needs      = "needs" "[" { key set "," } "]"
statement  = let | mut | fn | if | for | match | expr
let        = "let" name [ ":" type ] "=" expr
expr       = literal | path | name | call | list | record | expr "?" | expr "or" block
call       = name "(" [ expr { "," expr } ] ")"
list       = "[" [ expr { "," expr } ] "]"
record     = "{" [ name ":" expr { "," name ":" expr } ] "}"