Expression of type ExprTuple

from the theory of proveit.numbers.number_sets.integers

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, ExprTuple, Lambda, a, b
from proveit.logic import And, InSet
from proveit.numbers import Integer, Less, NaturalPos, subtract

# build up the expression from sub-expressions
expr = ExprTuple(Lambda([a, b], Conditional(InSet(subtract(a, b), NaturalPos), And(InSet(a, Integer), InSet(b, Integer), Less(b, 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())

\left(\left(a, b\right) \mapsto \left\{\left(a - b\right) \in \mathbb{N}^+ \textrm{ if } a \in \mathbb{Z} ,  b \in \mathbb{Z} ,  b < a\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: 2 body: 3
2	ExprTuple	23, 26
3	Conditional	value: 4 condition: 5
4	Operation	operator: 17 operands: 6
5	Operation	operator: 7 operands: 8
6	ExprTuple	9, 10
7	Literal
8	ExprTuple	11, 12, 13
9	Operation	operator: 14 operands: 15
10	Literal
11	Operation	operator: 17 operands: 16
12	Operation	operator: 17 operands: 18
13	Operation	operator: 19 operands: 20
14	Literal
15	ExprTuple	23, 21
16	ExprTuple	23, 22
17	Literal
18	ExprTuple	26, 22
19	Literal
20	ExprTuple	26, 23
21	Operation	operator: 24 operand: 26
22	Literal
23	Variable
24	Literal
25	ExprTuple	26
26	Variable