GNU Info

(guile.info)Equality

---

Next: Property Lists Up: Utility Functions

---

Enter node , (file) or (file)node

Equality
========

 - primitive: eq? x y
     Return `#t' iff X references the same object as Y.  `eq?' is
     similar to `eqv?' except that in some cases it is capable of
     discerning distinctions finer than those detectable by `eqv?'.

 - primitive: eqv? x y
     The `eqv?' procedure defines a useful equivalence relation on
     objects.  Briefly, it returns `#t' if X and Y should normally be
     regarded as the same object.  This relation is left slightly open
     to interpretation, but works for comparing immediate integers,
     characters, and inexact numbers.

 - primitive: equal? x y
     Return `#t' iff X and Y are recursively `eqv?' equivalent.
     `equal?' recursively compares the contents of pairs, vectors, and
     strings, applying `eqv?' on other objects such as numbers and
     symbols.  A rule of thumb is that objects are generally `equal?'
     if they print the same.  `equal?' may fail to terminate if its
     arguments are circular data structures.