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Expression of type Lambda

from the theory of proveit.logic.sets.enumeration

In [1]:
import proveit
# Automation is not needed when building an expression:
proveit.defaults.automation = False # This will speed things up.
proveit.defaults.inline_pngs = False # Makes files smaller.
%load_expr # Load the stored expression as 'stored_expr'
# import Expression classes needed to build the expression
from proveit import Conditional, Lambda, x
from proveit.logic import Equals, InSet, Or, Set
from proveit.numbers import one, three, two
In [2]:
# build up the expression from sub-expressions
expr = Lambda(x, Conditional(Or(Equals(x, one), Equals(x, two), Equals(x, three)), InSet(x, Set(one, two, three))))
expr:
In [3]:
# check that the built expression is the same as the stored expression
assert expr == stored_expr
assert expr._style_id == stored_expr._style_id
print("Passed sanity check: expr matches stored_expr")
Passed sanity check: expr matches stored_expr
In [4]:
# Show the LaTeX representation of the expression for convenience if you need it.
print(stored_expr.latex())
x \mapsto \left\{\left(x = 1\right) \lor \left(x = 2\right) \lor \left(x = 3\right) \textrm{ if } x \in \left\{1, 2, 3\right\}\right..
In [5]:
stored_expr.style_options()
no style options
In [6]:
# display the expression information
stored_expr.expr_info()
 core typesub-expressionsexpression
0Lambdaparameter: 19
body: 2
1ExprTuple19
2Conditionalvalue: 3
condition: 4
3Operationoperator: 5
operands: 6
4Operationoperator: 7
operands: 8
5Literal
6ExprTuple9, 10, 11
7Literal
8ExprTuple19, 12
9Operationoperator: 15
operands: 13
10Operationoperator: 15
operands: 14
11Operationoperator: 15
operands: 16
12Operationoperator: 17
operands: 18
13ExprTuple19, 20
14ExprTuple19, 21
15Literal
16ExprTuple19, 22
17Literal
18ExprTuple20, 21, 22
19Variable
20Literal
21Literal
22Literal