sagemathgh-36304: `sage.symbolics`: Remove code deprecated in sagemath#18036, sagemath#29738, sagemath#32386, sagemath#32638, sagemath#32665, sagemath#34215
    
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URL: sagemath#36304
Reported by: Matthias Köppe
Reviewer(s): David Coudert

Author: Release Manager

src/doc/en/reference/calculus/index.rst

@@ -53,7 +53,6 @@ Internal functionality supporting calculus
 - :doc:`sage/symbolic/function_factory`
 - :doc:`Internals of Callable Symbolic Expressions <sage/symbolic/callable>`
 - :doc:`sage/symbolic/expression_conversions`
-- :doc:`sage/symbolic/substitution_map`
 - :doc:`sage/symbolic/benchmark`
 - :doc:`sage/symbolic/random_tests`
 - :doc:`sage/symbolic/maxima_wrapper`
@@ -95,7 +94,6 @@ Internal functionality supporting calculus
    sage/calculus/var
    sage/symbolic/maxima_wrapper
    sage/symbolic/operators
-   sage/symbolic/substitution_map
    sage/symbolic/benchmark
    sage/symbolic/random_tests
 

src/sage/combinat/words/alphabet.py

@@ -32,15 +32,14 @@
 #                  http://www.gnu.org/licenses/
 # ****************************************************************************
 
-from sage.categories.sets_cat import Sets
+import collections.abc
 
-from sage.sets.totally_ordered_finite_set import TotallyOrderedFiniteSet
-from sage.sets.family import Family
-
-from sage.rings.integer import Integer
+from sage.categories.sets_cat import Sets
 from sage.rings.infinity import Infinity
-
+from sage.rings.integer import Integer
+from sage.sets.family import Family
 from sage.sets.non_negative_integers import NonNegativeIntegers
+from sage.sets.totally_ordered_finite_set import TotallyOrderedFiniteSet
 
 
 set_of_letters = {
@@ -222,7 +221,7 @@ def build_alphabet(data=None, names=None, name=None):
             return IntegerRange(Integer(data))
         if isinstance(names, str):
             return TotallyOrderedFiniteSet([names + '%d' % i for i in range(data)])
-        if len(names) == data:
+        if isinstance(names, collections.abc.Sequence) and len(names) == data:
             return TotallyOrderedFiniteSet(names)
         raise ValueError("invalid value for names")
 

src/sage/symbolic/all.py

@@ -1,10 +1,3 @@
-from sage.misc.lazy_import import lazy_import
-
-lazy_import("sage.symbolic.constants", "I", deprecation=(18036,
-        "import I from sage.symbolic.constants for the imaginary unit viewed as an element of SR, or from sage.rings.imaginary_unit for the element of ZZ[i]"))
-lazy_import("sage.symbolic.constants", "I", as_="i", deprecation=(18036,
-        "import I from sage.symbolic.constants for the imaginary unit viewed as an element of SR, or from sage.rings.imaginary_unit for the element of ZZ[i]"))
-
 from .ring import SR
 from .constants import (pi, e, NaN, golden_ratio, log2, euler_gamma, catalan,
                        khinchin, twinprime, mertens, glaisher)

src/sage/symbolic/callable.py

@@ -69,63 +69,6 @@
 ######################################################################
 #  Callable functions
 ######################################################################
-def is_CallableSymbolicExpressionRing(x):
-    """
-    Return ``True`` if ``x`` is a callable symbolic expression ring.
-
-    INPUT:
-
-    -  ``x`` - object
-
-    OUTPUT: bool
-
-    EXAMPLES::
-
-        sage: from sage.symbolic.callable import is_CallableSymbolicExpressionRing
-        sage: is_CallableSymbolicExpressionRing(QQ)
-        doctest:warning...
-        DeprecationWarning: is_CallableSymbolicExpressionRing is deprecated;
-        use isinstance(..., sage.rings.abc.CallableSymbolicExpressionRing instead
-        See https://github.com/sagemath/sage/issues/32665 for details.
-        False
-        sage: var('x,y,z')
-        (x, y, z)
-        sage: is_CallableSymbolicExpressionRing(CallableSymbolicExpressionRing((x,y,z)))
-        True
-    """
-    from sage.misc.superseded import deprecation
-    deprecation(32665, 'is_CallableSymbolicExpressionRing is deprecated; use isinstance(..., sage.rings.abc.CallableSymbolicExpressionRing instead')
-    return isinstance(x, CallableSymbolicExpressionRing_class)
-
-
-def is_CallableSymbolicExpression(x):
-    r"""
-    Return ``True`` if ``x`` is a callable symbolic expression.
-
-    EXAMPLES::
-
-        sage: from sage.symbolic.callable import is_CallableSymbolicExpression
-        sage: var('a x y z')
-        (a, x, y, z)
-        sage: f(x,y) = a + 2*x + 3*y + z
-        sage: is_CallableSymbolicExpression(f)
-        doctest:warning...
-        DeprecationWarning: is_CallableSymbolicExpression is deprecated;
-        use isinstance(..., Expression) and ....is_callable() instead
-        See https://github.com/sagemath/sage/issues/34215 for details.
-        True
-        sage: is_CallableSymbolicExpression(a+2*x)
-        False
-        sage: def foo(n): return n^2
-        ...
-        sage: is_CallableSymbolicExpression(foo)
-        False
-    """
-    from sage.misc.superseded import deprecation
-    deprecation(34215, 'is_CallableSymbolicExpression is deprecated; use isinstance(..., Expression) and ....is_callable() instead')
-    from sage.structure.element import Expression
-    return isinstance(x, Expression) and isinstance(x.parent(), CallableSymbolicExpressionRing_class)
-
 
 class CallableSymbolicExpressionFunctor(ConstructionFunctor):
     def __init__(self, arguments):

src/sage/symbolic/comparison.py

@@ -1,4 +1,3 @@
-cpdef bint is_Expression(x)
 cpdef _repr_Expression(x)
 cpdef _latex_Expression(x)
 cpdef new_Expression(parent, x)

src/sage/symbolic/constant.py

@@ -409,32 +409,6 @@ include "pynac_impl.pxi"
 from sage.symbolic.symbols import symbol_table, register_symbol  # used to be defined in pynac_impl
 
 
-cpdef bint is_Expression(x):
-    """
-    Return True if ``x`` is a symbolic expression.
-
-    This method is deprecated.  Use :func:`isinstance` with
-    :class:`sage.structure.element.Expression` instead.
-
-    EXAMPLES::
-
-        sage: from sage.symbolic.expression import is_Expression
-        sage: is_Expression(x)
-        doctest:warning...
-        DeprecationWarning: is_Expression is deprecated;
-        use isinstance(..., sage.structure.element.Expression) instead
-        See https://github.com/sagemath/sage/issues/32638 for details.
-        True
-        sage: is_Expression(2)
-        False
-        sage: is_Expression(SR(2))
-        True
-    """
-    from sage.misc.superseded import deprecation
-    deprecation(32638, 'is_Expression is deprecated; use isinstance(..., sage.structure.element.Expression) instead')
-    return isinstance(x, Expression)
-
-
 cpdef bint is_SymbolicEquation(x):
     """
     Return True if *x* is a symbolic equation.
@@ -6346,32 +6320,6 @@ cdef class Expression(Expression_abc):
 
     nops = number_of_operands
 
-    def __len__(self):
-        """
-        Return the number of operands of this expression.
-
-        This is deprecated; use :meth:`number_of_operands` instead.
-
-        EXAMPLES::
-
-            sage: var('a,b,c,x,y')
-            (a, b, c, x, y)
-            sage: len(a)
-            doctest:warning...
-            DeprecationWarning: using len on a symbolic expression is deprecated; use method number_of_operands instead
-            See https://github.com/sagemath/sage/issues/29738 for details.
-            0
-            sage: len((a^2 + b^2 + (x+y)^2))
-            3
-            sage: len((a^2))
-            2
-            sage: len(a*b^2*c)
-            3
-        """
-        from sage.misc.superseded import deprecation
-        deprecation(29738, "using len on a symbolic expression is deprecated; use method number_of_operands instead")
-        return self.number_of_operands()
-
     def _unpack_operands(self):
         """
         Unpack the operands of this expression converting each to a Python