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Errors

Keel aims to have pretty (thanks Ariadne!) and helpful error messages. Currently, some error messages are more helpful than others. This is a work in progress, and error messages will continue to improve over time. 

struct Point {
    x:float,
    y:float,
    z:float
}

fn main() {
    let origin = Point {x: 0.0, y: 0.0, z: 0.0};
    origin.x = 10;
}

-- OUTPUT -- 
Error: Incompatible types
   ╭─[ testing/error.kl:2:7 ]
   │
 2 │     x:float,
   │       ───┬──
   │          ╰──── Field x in struct Point expects type float
   │
 9 │     origin.x = 10;
   │                ─┬
   │                 ╰── This expression is of type int
   │
   │ Help: Try using the float() function
───╯

List of catchable errors

Misc

  • division_by_zero
  • modulo_by_zero
  • index_out_of_bounds
  • slice_out_of_bounds
  • unknown_map_key
  • integer_negative_exponent (will be available with the release of Keel 0.5)

Runtime parsing

  • invalid_float
  • invalid_int
  • invalid_bool

File system

  • fs_already_exists
  • fs_deadlock
  • fs_file_too_large
  • fs_interrupted
  • fs_invalid_data
  • fs_invalid_filename
  • fs_is_a_directory
  • fs_not_a_directory
  • fs_not_found
  • fs_permission_denied
  • fs_out_of_memory
  • fs_read_only_filesystem
  • fs_storage_full
  • fs_timed_out
  • fs_other (will be available with the release of Keel 0.5)

FFI

  • null_byte_in_string
  • invalid_return_type