# ____________________________________________________________________________________
#
# Pyomo: Python Optimization Modeling Objects
# Copyright (c) 2008-2026 National Technology and Engineering Solutions of Sandia, LLC
# Under the terms of Contract DE-NA0003525 with National Technology and Engineering
# Solutions of Sandia, LLC, the U.S. Government retains certain rights in this
# software. This software is distributed under the 3-clause BSD License.
# ____________________________________________________________________________________
from pyomo.core.expr.logical_expr import BooleanExpression
[docs]
class PrecedenceExpression(BooleanExpression):
PRECEDENCE = None
[docs]
def nargs(self):
return 3
@property
def delay(self):
return self._args_[2]
def _to_string_impl(self, values, relation):
delay = values[2]
if delay == '0':
first = values[0]
elif delay[0] in '-+':
first = "%s %s %s" % (values[0], delay[0], delay[1:])
else:
first = "%s + %s" % (values[0], delay)
return "%s %s %s" % (first, relation, values[1])
[docs]
class BeforeExpression(PrecedenceExpression):
"""
Base class for all precedence expressions.
args:
args (tuple): child nodes of type IntervalVar. We expect them to be
(time_that_comes_before, time_that_comes_after, delay).
delay: A (possibly negative) integer value representing the number of
time periods delay in the precedence relationship
"""
def _to_string(self, values, verbose, smap):
return self._to_string_impl(values, "<=")
[docs]
class AtExpression(PrecedenceExpression):
"""
Base class for all precedence expressions.
args:
args (tuple): child nodes of type IntervalVar. We expect them to be
(first_time, second_time, delay).
delay: A (possibly negative) integer value representing the number of
time periods delay in the precedence relationship
"""
def _to_string(self, values, verbose, smap):
return self._to_string_impl(values, "==")