Expression of type Lambda

from the theory of proveit.logic.booleans.disjunction

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, ExprRange, Function, Lambda, P, Pk, Variable, i, j, k
from proveit.logic import And, Exists, Forall, Implies, InSet, Or
from proveit.numbers import Integer, Interval

# build up the expression from sub-expressions
sub_expr1 = Variable("_a", latex_format = r"{_{-}a}")
expr = Lambda([i, j], Conditional(Forall(instance_param_or_params = [P], instance_expr = Implies(Or(ExprRange(sub_expr1, Function(P, [sub_expr1]), i, j)), Exists(instance_param_or_params = [k], instance_expr = Pk, domain = Interval(i, j)))), And(InSet(i, Integer), InSet(j, Integer))))

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(i, j\right) \mapsto \left\{\forall_{P}~\left(\left(P\left(i\right) \lor  P\left(i + 1\right) \lor  \ldots \lor  P\left(j\right)\right) \Rightarrow \left[\exists_{k \in \{i~\ldotp \ldotp~j\}}~P\left(k\right)\right]\right) \textrm{ if } i \in \mathbb{Z} ,  j \in \mathbb{Z}\right..

stored_expr.style_options()

no style options

# display the expression information
stored_expr.expr_info()

	core type	sub-expressions	expression
0	Lambda	parameters: 40 body: 1
1	Conditional	value: 2 condition: 3
2	Operation	operator: 4 operand: 8
3	Operation	operator: 6 operands: 7
4	Literal
5	ExprTuple	8
6	Literal
7	ExprTuple	9, 10
8	Lambda	parameter: 32 body: 12
9	Operation	operator: 34 operands: 13
10	Operation	operator: 34 operands: 14
11	ExprTuple	32
12	Operation	operator: 15 operands: 16
13	ExprTuple	41, 17
14	ExprTuple	42, 17
15	Literal
16	ExprTuple	18, 19
17	Literal
18	Operation	operator: 20 operands: 21
19	Operation	operator: 22 operand: 25
20	Literal
21	ExprTuple	24
22	Literal
23	ExprTuple	25
24	ExprRange	lambda_map: 26 start_index: 41 end_index: 42
25	Lambda	parameter: 37 body: 27
26	Lambda	parameter: 36 body: 28
27	Conditional	value: 29 condition: 30
28	Operation	operator: 32 operand: 36
29	Operation	operator: 32 operand: 37
30	Operation	operator: 34 operands: 35
31	ExprTuple	36
32	Variable
33	ExprTuple	37
34	Literal
35	ExprTuple	37, 38
36	Variable
37	Variable
38	Operation	operator: 39 operands: 40
39	Literal
40	ExprTuple	41, 42
41	Variable
42	Variable