Expression of type Lambda

from the theory of proveit.logic.booleans.negation

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 A, Conditional, Lambda
from proveit.logic import And, Boolean, InSet, Not

# build up the expression from sub-expressions
expr = Lambda(A, Conditional(A, And(InSet(A, Boolean), Not(Not(A)))))

expr:

# 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

# Show the LaTeX representation of the expression for convenience if you need it.
print(stored_expr.latex())

A \mapsto \left\{A \textrm{ if } A \in \mathbb{B} ,  \lnot (\lnot A)\right..

stored_expr.style_options()

no style options

# display the expression information
stored_expr.expr_info()

	core type	sub-expressions	expression
0	Lambda	parameter: 14 body: 1
1	Conditional	value: 14 condition: 2
2	Operation	operator: 3 operands: 4
3	Literal
4	ExprTuple	5, 6
5	Operation	operator: 7 operands: 8
6	Operation	operator: 12 operand: 11
7	Literal
8	ExprTuple	14, 10
9	ExprTuple	11
10	Literal
11	Operation	operator: 12 operand: 14
12	Literal
13	ExprTuple	14
14	Variable