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Expression of type Lambda

from the theory of proveit.logic.sets.enumeration

In [1]:
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 Lambda, P, Px, x
from proveit.core_expr_types import Pk_a1_to_an, a_1_to_n
from proveit.logic import Forall, Set
In [2]:
# build up the expression from sub-expressions
expr = Lambda([a_1_to_n], Forall(instance_param_or_params = [P], instance_expr = Forall(instance_param_or_params = [x], instance_expr = Px, domain = Set(a_1_to_n)), condition = Pk_a1_to_an))
expr:
In [3]:
# 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
In [4]:
# Show the LaTeX representation of the expression for convenience if you need it.
print(stored_expr.latex())
\left(a_{1}, a_{2}, \ldots, a_{n}\right) \mapsto \left[\forall_{P~|~P\left(a_{1}\right), P\left(a_{2}\right), \ldots, P\left(a_{n}\right)}~\left[\forall_{x \in \left\{a_{1}, a_{2}, \ldots, a_{n}\right\}}~P\left(x\right)\right]\right]
In [5]:
stored_expr.style_options()
no style options
In [6]:
# display the expression information
stored_expr.expr_info()
 core typesub-expressionsexpression
0Lambdaparameters: 27
body: 1
1Operationoperator: 8
operand: 3
2ExprTuple3
3Lambdaparameter: 22
body: 5
4ExprTuple22
5Conditionalvalue: 6
condition: 7
6Operationoperator: 8
operand: 12
7Operationoperator: 10
operands: 11
8Literal
9ExprTuple12
10Literal
11ExprTuple13
12Lambdaparameter: 24
body: 14
13ExprRangelambda_map: 15
start_index: 30
end_index: 31
14Conditionalvalue: 16
condition: 17
15Lambdaparameter: 35
body: 18
16Operationoperator: 22
operand: 24
17Operationoperator: 20
operands: 21
18Operationoperator: 22
operand: 32
19ExprTuple24
20Literal
21ExprTuple24, 25
22Variable
23ExprTuple32
24Variable
25Operationoperator: 26
operands: 27
26Literal
27ExprTuple28
28ExprRangelambda_map: 29
start_index: 30
end_index: 31
29Lambdaparameter: 35
body: 32
30Literal
31Variable
32IndexedVarvariable: 33
index: 35
33Variable
34ExprTuple35
35Variable