Expression of type Lambda

from the theory of proveit.core_expr_types.conditionals

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, Q
from proveit.logic import Implies

# build up the expression from sub-expressions
expr = Lambda([A, Q], Conditional(Implies(Q, A), Conditional(A, Q)))

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())

\left(A, Q\right) \mapsto \left\{Q \Rightarrow A \textrm{ if } \left\{A \textrm{ if } Q\right..\right..

stored_expr.style_options()

no style options

# display the expression information
stored_expr.expr_info()

	core type	sub-expressions	expression
0	Lambda	parameters: 1 body: 2
1	ExprTuple	8, 7
2	Conditional	value: 3 condition: 4
3	Operation	operator: 5 operands: 6
4	Conditional	value: 8 condition: 7
5	Literal
6	ExprTuple	7, 8
7	Variable
8	Variable