Expression of type Lambda

from the theory of proveit.logic.sets.enumeration

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

# 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:

# 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())

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..

stored_expr.style_options()

no style options

# display the expression information
stored_expr.expr_info()

	core type	sub-expressions	expression
0	Lambda	parameter: 19 body: 2
1	ExprTuple	19
2	Conditional	value: 3 condition: 4
3	Operation	operator: 5 operands: 6
4	Operation	operator: 7 operands: 8
5	Literal
6	ExprTuple	9, 10, 11
7	Literal
8	ExprTuple	19, 12
9	Operation	operator: 15 operands: 13
10	Operation	operator: 15 operands: 14
11	Operation	operator: 15 operands: 16
12	Operation	operator: 17 operands: 18
13	ExprTuple	19, 20
14	ExprTuple	19, 21
15	Literal
16	ExprTuple	19, 22
17	Literal
18	ExprTuple	20, 21, 22
19	Variable
20	Literal
21	Literal
22	Literal