.TH "Stdlib.Repr" 3 2025-06-09 OCamldoc "OCaml library"
.SH NAME
Stdlib.Repr \- no description
.SH Module
Module   Stdlib.Repr
.SH Documentation
.sp
Module
.BI "Repr"
 : 
.B (module Stdlib__Repr)

.sp

.sp

.sp
.sp

.PP
.SS Physical comparison

.PP

.I val phys_equal 
: 
.B 'a -> 'a -> bool
.sp

.ft B
phys_equal e1 e2
.ft R
tests for physical equality of 
.ft B
e1
.ft R
and 
.ft B
e2
.ft R
\&.
On mutable types such as references, arrays, byte sequences, records with
mutable fields and objects with mutable instance variables,
.ft B
phys_equal e1 e2
.ft R
is true if and only if physical modification of 
.ft B
e1
.ft R
also affects 
.ft B
e2
.ft R
\&.
On non\-mutable types, the behavior of 
.ft B
phys_equal
.ft R
is
implementation\-dependent; however, it is guaranteed that
.ft B
phys_equal e1 e2
.ft R
implies 
.ft B
compare e1 e2 = 0
.ft R
\&.

.sp

.PP
.SS Polymorphic comparison

.PP

.I val equal 
: 
.B 'a -> 'a -> bool
.sp

.ft B
equal e1 e2
.ft R
tests for structural equality of 
.ft B
e1
.ft R
and 
.ft B
e2
.ft R
\&.
Mutable structures (e\&.g\&. references and arrays) are equal
if and only if their current contents are structurally equal,
even if the two mutable objects are not the same physical object\&.
Equality between functional values raises 
.ft B
Invalid_argument
.ft R
\&.
Equality between cyclic data structures may not terminate\&.

.sp

.I val compare 
: 
.B 'a -> 'a -> int
.sp

.ft B
compare x y
.ft R
returns 
.ft B
0
.ft R
if 
.ft B
x
.ft R
is equal to 
.ft B
y
.ft R
,
a negative integer if 
.ft B
x
.ft R
is less than 
.ft B
y
.ft R
, and a positive integer
if 
.ft B
x
.ft R
is greater than 
.ft B
y
.ft R
\&.  The ordering implemented by 
.ft B
compare
.ft R
is compatible with the comparison predicates 
.ft B
(=)
.ft R
,
.ft B
(<)
.ft R
and 
.ft B
(>)
.ft R
, as well as the 
.ft B
equal
.ft R
function
defined above,  with one difference on the treatment of the float value
.ft B
nan
.ft R
\&.  Namely, the comparison predicates treat 
.ft B
nan
.ft R
as different from any other float value, including itself;
while 
.ft B
repr
.ft R
treats 
.ft B
nan
.ft R
as equal to itself and less than any
other float value\&.  This treatment of 
.ft B
nan
.ft R
ensures that 
.ft B
compare
.ft R
defines a total ordering relation\&.
.sp

.ft B
compare
.ft R
applied to functional values may raise 
.ft B
Invalid_argument
.ft R
\&.
.ft B
compare
.ft R
applied to cyclic structures may not terminate\&.
.sp
The 
.ft B
compare
.ft R
function can be used as the comparison function
required by the 
.ft B
Set\&.Make
.ft R
and 
.ft B
Map\&.Make
.ft R
functors, as well as
the 
.ft B
List\&.sort
.ft R
and 
.ft B
Array\&.sort
.ft R
functions\&.

.sp

.I val min 
: 
.B 'a -> 'a -> 'a
.sp
Return the smaller of the two arguments\&.
The result is unspecified if one of the arguments contains
the float value 
.ft B
nan
.ft R
\&.

.sp

.I val max 
: 
.B 'a -> 'a -> 'a
.sp
Return the greater of the two arguments\&.
The result is unspecified if one of the arguments contains
the float value 
.ft B
nan
.ft R
\&.

.sp