Expression of type Lambda

from the theory of proveit.core_expr_types.lambda_maps

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 Composition, Lambda, f, fx, fy, g, x, y
from proveit.logic import Equals

# build up the expression from sub-expressions
expr = Lambda([f, g], Equals(Composition(Lambda(x, fx)), Lambda(y, fy)))

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(f, g\right) \mapsto \left(\left[\circ\right]\left(x \mapsto f\left(x\right)\right) = \left[y \mapsto f\left(y\right)\right]\right)

stored_expr.style_options()

no style options

# display the expression information
stored_expr.expr_info()

	core type	sub-expressions	expression
0	Lambda	parameters: 1 body: 2
1	ExprTuple	14, 3
2	Operation	operator: 4 operands: 5
3	Variable
4	Literal
5	ExprTuple	6, 10
6	Operation	operator: 7 operand: 10
7	Literal
8	ExprTuple	10
9	Operation	operator: 14 operand: 13
10	Lambda	parameter: 16 body: 12
11	ExprTuple	13
12	Operation	operator: 14 operand: 16
13	Variable
14	Variable
15	ExprTuple	16
16	Variable