2.4 The Solvers

suspend

This is the simplest possible ’solver’. Its behaviour is to wait until
all variables in a constraint have been instantiated to numbers.
Then it performs a test to check whether the constraint is satisfied,
and fails if this is not the case.
 ic

A hybrid solver, combining integer and real interval constraint
solving. This solver replaces the older FD solver.
For more information, please see chapter 3.
 gfd

An integer finite domain solver, implemented via interfacing
to the third party Gecode software.
For more information, please see chapter 7.
 fd

Obsolescent integer finite domain solver.
 eplex

An interface to an LP or MIP solver, i.e. it implements linear
constraints over reals or integers.
 standard arithmetic

This is not really a solver, but just the implementation of simple
arithmetic tests in module eclipse_language. These require
that all variables are instantiated when the test is invoked.
The reason to list it here is that the arithmetic constraints
can be considered generalisations of these traditional tests.