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| author | Gabriel Scherer <gabriel.scherer@gmail.com> | 2014-01-09 16:24:32 +0000 |
|---|---|---|
| committer | Gabriel Scherer <gabriel.scherer@gmail.com> | 2014-01-09 16:24:32 +0000 |
| commit | a2f40d86765e7697321f22427997060a443d0548 (patch) | |
| tree | c21042dc881b89f14d9990578598a74f3cd682e5 /otherlibs/bigarray/bigarray.mli | |
| parent | 844052b22ea80f7cb5f0b9c20c89469423679902 (diff) | |
make bigarray.mli's documentation consistent with the new GADT interface
git-svn-id: http://caml.inria.fr/svn/ocaml/trunk@14392 f963ae5c-01c2-4b8c-9fe0-0dff7051ff02
Diffstat (limited to 'otherlibs/bigarray/bigarray.mli')
| -rw-r--r-- | otherlibs/bigarray/bigarray.mli | 51 |
1 files changed, 33 insertions, 18 deletions
diff --git a/otherlibs/bigarray/bigarray.mli b/otherlibs/bigarray/bigarray.mli index f25a6d41d..058c25904 100644 --- a/otherlibs/bigarray/bigarray.mli +++ b/otherlibs/bigarray/bigarray.mli @@ -52,8 +52,9 @@ - platform-native signed integers (32 bits on 32-bit architectures, 64 bits on 64-bit architectures) ({!Bigarray.nativeint_elt}). - Each element kind is represented at the type level by one - of the abstract types defined below. + Each element kind is represented at the type level by one of the + [*_elt] types defined below (defined with a single constructor instead + of abstract types for technical injectivity reasons). *) type float32_elt = Float32_elt @@ -92,12 +93,28 @@ type ('a, 'b) kind = its elements from OCaml uses the OCaml type [float], which is 64-bit double precision floats. - The abstract type [('a, 'b) kind] captures this association + The GADT type [('a, 'b) kind] captures this association of an OCaml type ['a] for values read or written in the big array, and of an element kind ['b] which represents the actual contents - of the big array. The following predefined values of type - [kind] list all possible associations of OCaml types with - element kinds: *) + of the big array. Its constructors list all possible associations + of OCaml types with element kinds, and are re-exported below for + backward-compatibility reasons. + + Using a generalized algebraic datatype (GADT) here allows to write + well-typed polymorphic functions whose return type depend on the + argument type, such as: + +{[ + let zero : type a b. (a, b) kind -> a = function + | Float32 -> 0.0 | Complex32 -> Complex.zero + | Float64 -> 0.0 | Complex64 -> Complex.zero + | Int8_signed -> 0 | Int8_unsigned -> 0 + | Int16_signed -> 0 | Int16_unsigned -> 0 + | Int32 -> 0l | Int64 -> 0L + | Int -> 0 | Nativeint -> 0n + | Char -> '\000' +]} +*) val float32 : (float, float32_elt) kind (** See {!Bigarray.char}. *) @@ -140,7 +157,7 @@ val char : (char, int8_unsigned_elt) kind big arrays of kind [float32_elt] and [float64_elt] are accessed using the OCaml type [float]. Big arrays of complex kinds [complex32_elt], [complex64_elt] are accessed with the OCaml type - {!Complex.t}. Big arrays of + {!Complex.t}. Big arrays of integer kinds are accessed using the smallest OCaml integer type large enough to represent the array elements: [int] for 8- and 16-bit integer bigarrays, as well as OCaml-integer @@ -177,22 +194,20 @@ type fortran_layout = Fortran_layout_typ and [(x+1, y)] are adjacent in memory. Each layout style is identified at the type level by the - abstract types {!Bigarray.c_layout} and [fortran_layout] respectively. *) - -type 'a layout = - C_layout: c_layout layout - | Fortran_layout: fortran_layout layout -(** The type ['a layout] represents one of the two supported - memory layouts: C-style if ['a] is {!Bigarray.c_layout}, Fortran-style - if ['a] is {!Bigarray.fortran_layout}. *) - + phantom types {!Bigarray.c_layout} and {!Bigarray.fortran_layout} + respectively. *) (** {7 Supported layouts} - The abstract values [c_layout] and [fortran_layout] represent - the two supported layouts at the level of values. + The GADT type ['a layout] represents one of the two supported + memory layouts: C-style or Fortran-style. Its constructors are + re-exported as values below for backward-compatibility reasons. *) +type 'a layout = + C_layout: c_layout layout + | Fortran_layout: fortran_layout layout + val c_layout : c_layout layout val fortran_layout : fortran_layout layout |