Expression of type Lambda

from the theory of proveit.numbers.number_sets.rational_numbers

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, q
from proveit.logic import And, InSet
from proveit.numbers import Rational, greater_eq, zero

# build up the expression from sub-expressions
expr = Lambda(q, Conditional(q, And(InSet(q, Rational), greater_eq(q, zero))))

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())

q \mapsto \left\{q \textrm{ if } q \in \mathbb{Q} ,  q \geq 0\right..

stored_expr.style_options()

no style options

# display the expression information
stored_expr.expr_info()

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