Mapytex/pymath/calculus/operator/operator.py

#!/usr/bin/env python
# encoding: utf-8

# from debug.tools import report

from ..generic import flatten_list


class Operator():

    """The operator class, is a string (representation of the operator) with its arity"""

    def __init__(self, operator="", name="", priority=0, actions=("", ""), txt="", tex="", arity=2, **kwrds):
        """ Create an Operator """
        self.operator = operator
        self.name = name
        self.arity = arity
        self.priority = priority
        self.actions = actions
        self.txt = txt
        self.tex = tex

        self.isOperator = 1

    def __call__(self, *args):
        """ Calling this operator performs the rigth calculus """
        if self.arity == 1:
            return getattr(args[0], self.actions)()

        elif self.arity == 2:
            if issubclass(type(args[1]), int):
                return getattr(args[0], self.actions[0])(args[1])
            else:
                return getattr(args[1], self.actions[1])(args[0])

    def _render(self, link, *args):
        """Global step for __txt__ and __tex__

        :param link: the link between operators
        :param *args: the operands
        :returns: the string with operator and operands

        """
        if self.arity == 1:
            op1 = self.l_parenthesis(args[0], True)
            ans = link.format(op1=op1)

        elif self.arity == 2:
            op1 = self.l_parenthesis(args[0], True)
            op2 = self.r_parenthesis(args[1], True)
            ans = link.format(op1=op1, op2=op2)

        ans = save_mainOp(ans, self)
        return ans

    def __repr__(self):
        return str(self.operator)

    def __str__(self):
        return str(self.operator)

    def __txt__(self, *args):
        """Txt rendering for the operator

        :*args: Operands for this operation
        :returns: String with operator and his operands

        >>> from .mul import Mul
        >>> mul= Mul()
        >>> from .add import Add
        >>> add = Add()
        >>> from .sub import Sub
        >>> sub = Sub()
        >>> from .sub1 import Sub1
        >>> sub1 = Sub1()
        >>> mul.__txt__('1','2')
        '1 * 2'
        >>> add.__txt__('1','2')
        '1 + 2'
        >>> f = save_mainOp('2 + 3',add)
        >>> mul.__txt__(f, '4')
        '( 2 + 3 ) * 4'
        >>> f = save_mainOp('-3',sub1)
        >>> sub1.__txt__(f)
        '- ( -3 )'
        >>> sub1.__txt__('-3')
        '- ( -3 )'
        >>> f = save_mainOp('2 + 3',add)
        >>> sub1.__txt__(f)
        '- ( 2 + 3 )'
        """
        return self._render(self.txt, *args)

    def __tex__(self, *args):
        """Tex rendering for the operator

        :*args: Operands for this operation
        :returns: String with operator and his operands

        >>> from .mul import Mul
        >>> mul= Mul()
        >>> from .add import Add
        >>> add = Add()
        >>> from .sub import Sub
        >>> sub = Sub()
        >>> from .sub1 import Sub1
        >>> sub1 = Sub1()
        >>> mul.__tex__('1','2')
        '1 \\\\times 2'
        >>> add.__tex__('1','2')
        '1 + 2'
        >>> f = save_mainOp('2 + 3',add)
        >>> mul.__tex__(f, '4')
        '( 2 + 3 ) \\\\times 4'
        >>> f = save_mainOp('-3',sub1)
        >>> sub1.__tex__(f)
        '- ( -3 )'
        >>> sub1.__tex__('-3')
        '- ( -3 )'
        >>> f = save_mainOp('2 + 3',add)
        >>> sub1.__tex__(f)
        '- ( 2 + 3 )'
        """
        return self._render(self.tex, *args)

    def __p2i__(self, *args):
        """Fix list transformation for the operator

        :*args: Operands for this operation
        :returns: list with the operator surrounded by operands

        >>> from .mul import Mul
        >>> mul= Mul()
        >>> from .add import Add
        >>> add = Add()
        >>> from .sub import Sub
        >>> sub = Sub()
        >>> from .sub1 import Sub1
        >>> sub1 = Sub1()
        >>> mul.__p2i__(1,2)
        [1, *, 2]
        >>> f = save_mainOp([2, add, 3],add)
        >>> mul.__p2i__(f, 4)
        ['(', 2, +, 3, ')', *, 4]
        >>> f = save_mainOp([sub1, 3],sub1)
        >>> sub1.__p2i__(f)
        [-, '(', -, 3, ')']
        >>> sub1.__p2i__(-3)
        [-, '(', -3, ')']
        >>> f = save_mainOp([2, add, 3],add)
        >>> sub1.__p2i__(f)
        [-, '(', 2, +, 3, ')']
        """
        if self.arity == 1:
            op1 = self.l_parenthesis(args[0])
            ans = flatten_list([self, op1])

        elif self.arity == 2:
            op1 = self.l_parenthesis(args[0])
            op2 = self.r_parenthesis(args[1])
            ans = flatten_list([op1, self, op2])

        ans = save_mainOp(ans, self)
        return ans

    def l_parenthesis(self, opl, str_join=False):
        """ Add parenthesis for left operand if necessary """
        ans = opl
        try:
            if opl.mainOp.name == "sub1":
                ans = opl
            elif opl.mainOp.priority < self.priority:
                ans = flatten_list(["(", opl, ")"])
        except AttributeError:
            # op has not the attribute priority
            pass

        ans = flatten_list([ans])
        if str_join:
            ans = ' '.join([str(i) for i in ans])
        return ans

    def r_parenthesis(self, opr, str_join=False):
        """ Add parenthesis for rigth operand if necessary """
        ans = opr
        try:
            if opr.mainOp.priority < self.priority or \
                (opr.mainOp.name == 'mul' and opr[0] == '-'):
                ans = flatten_list(["(", ans, ")"])
        except AttributeError:
            # op has not the attribute priority
            try:
                if int(ans) < 0:
                    ans = ['(', ans, ')']
            except ValueError:
                pass
        ans = flatten_list([ans])
        if str_join:
            ans = ' '.join([str(i) for i in ans])
        return ans

    def uniq_desc(self):
        """ Return the uniq description of the operator
        :returns: (self.name, self.arity)

        """
        return (self.operator, self.arity)

    def __eq__(self, op2):
        """ op1 == op2 """
        try:
            return self.name == op2.name and self.arity == op2.arity
        except AttributeError:
            return False


def save_mainOp(obj, mainOp):
    """Create a temporary class build over built-in type to stock the main operation of a calculus

    :obj: the object to add the attribute
    :mainOp: the main operator
    :returns: the same object with the main operation attribute
    """
    # TODO: À mettre avec render? |mar. févr. 23 09:45:22 EAT 2016
    # TODO: On pourrait mettre un try avant de créer une nouvelle classe |mar. févr. 23 09:44:45 EAT 2016
    Fake = type('fake_'+str(type(obj)), (type(obj),), {'mainOp': mainOp})

    return Fake(obj)


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