Module Ecaml.Position

A "position" is the index of a character in the text of a buffer. More precisely, a position identifies the place between two characters (or before the first character, or after the last character), so we can speak of the character before or after a given position. However, we often speak of the character "at" a position, meaning the character after that position.

Positions are usually represented as integers starting from 1, but can also be represented as "markers"--special objects that relocate automatically when text is inserted or deleted so they stay with the surrounding characters.

(Info-goto-node "(elisp)Positions").

include Value.Subtype
type value
type 'a type_
type t = private value

We expose private value for free identity conversions when the value is nested in some covariant type, e.g. (symbols : Symbol.t list :> Value.t list) rather than List.map symbols ~f:Symbol.to_value.

include sig ... end
val sexp_of_t : t ‑> Sexplib.Sexp.t
val of_value_exn : value ‑> t
val to_value : t ‑> value
val eq : t ‑> t ‑> bool

eq t1 t2 = Value.eq (to_value t1) (to_value t2), i.e. eq checks whether the Emacs values underlying t1 and t2 are physically equal. This is different than phys_equal t1 t2, because we don't always wrap eq Emacs values in phys_equal OCaml values. I.e. phys_equal t1 t2 implies eq t1 t2, but not the converse.

val type_ : t type_
include Core_kernel.Comparable.S_plain with type t := t
include Core_kernel__.Comparable_intf.S_common
include Base.Comparable_intf.S
include Base.Comparable_intf.Polymorphic_compare
include Base.Comparisons.Infix
type t
val (>=) : t ‑> t ‑> bool
val (<=) : t ‑> t ‑> bool
val (=) : t ‑> t ‑> bool
val (>) : t ‑> t ‑> bool
val (<) : t ‑> t ‑> bool
val (<>) : t ‑> t ‑> bool
val equal : t ‑> t ‑> bool
val compare : t ‑> t ‑> int

compare t1 t2 returns 0 if t1 is equal to t2, a negative integer if t1 is less than t2, and a positive integer if t1 is greater than t2.

val min : t ‑> t ‑> t
val max : t ‑> t ‑> t
val ascending : t ‑> t ‑> int

ascending is identical to compare. descending x y = ascending y x. These are intended to be mnemonic when used like List.sort ~cmp:ascending and List.sort ~cmp:descending, since they cause the list to be sorted in ascending or descending order, respectively.

val descending : t ‑> t ‑> int
val between : t ‑> low:t ‑> high:t ‑> bool
val clamp_exn : t ‑> min:t ‑> max:t ‑> t

clamp_exn t ~min ~max returns t', the closest value to t such that between t' ~low:min ~high:max is true.

Raises if not (min <= max).

val clamp : t ‑> min:t ‑> max:t ‑> t Base.Or_error.t
include Base.Comparator.S with type t := t
type t
type comparator_witness
include Base.Comparable_intf.Validate with type t := t
type t
val validate_lbound : min:t Base.Maybe_bound.t ‑> t Base.Validate.check
val validate_ubound : max:t Base.Maybe_bound.t ‑> t Base.Validate.check
val validate_bound : min:t Base.Maybe_bound.t ‑> max:t Base.Maybe_bound.t ‑> t Base.Validate.check
val of_int_exn : int ‑> t
val to_int : t ‑> int
val add : t ‑> int ‑> t
val sub : t ‑> int ‑> t
val diff : t ‑> t ‑> int