Expression of type ExprTuple

from the theory of proveit.core_expr_types.tuples

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 ExprTuple, Lambda, b, i
from proveit.core_expr_types import Len, a_1_to_i
from proveit.logic import Equals
from proveit.numbers import Add, one

# build up the expression from sub-expressions
sub_expr1 = [a_1_to_i, b]
expr = ExprTuple(Lambda(sub_expr1, Equals(Len(operands = sub_expr1), Add(i, one))))

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(\left(a_{1}, a_{2}, \ldots, a_{i}, b\right) \mapsto \left(|\left(a_{1}, a_{2}, \ldots, a_{i}, b\right)| = \left(i + 1\right)\right)\right)

stored_expr.style_options()

no style options

# display the expression information
stored_expr.expr_info()

	core type	sub-expressions	expression
0	ExprTuple	1
1	Lambda	parameters: 8 body: 2
2	Operation	operator: 3 operands: 4
3	Literal
4	ExprTuple	5, 6
5	Operation	operator: 7 operands: 8
6	Operation	operator: 9 operands: 10
7	Literal
8	ExprTuple	11, 12
9	Literal
10	ExprTuple	15, 14
11	ExprRange	lambda_map: 13 start_index: 14 end_index: 15
12	Variable
13	Lambda	parameter: 19 body: 16
14	Literal
15	Variable
16	IndexedVar	variable: 17 index: 19
17	Variable
18	ExprTuple	19
19	Variable