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Expression of type Lambda

from the theory of proveit.logic.booleans.quantification.existence

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, Q
from proveit.logic import Equals
from proveit.logic.booleans.quantification import general_forall__Py_not_T__st_Qy, general_notexists_Px_st_Qx
In [2]:
# build up the expression from sub-expressions
expr = Lambda([P, Q], Equals(general_notexists_Px_st_Qx, general_forall__Py_not_T__st_Qy).with_wrapping_at(2))
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(P, Q\right) \mapsto \left(\begin{array}{c} \begin{array}{l} \left[\nexists_{x_{1}, x_{2}, \ldots, x_{n}~|~Q\left(x_{1}, x_{2}, \ldots, x_{n}\right)}~P\left(x_{1}, x_{2}, \ldots, x_{n}\right)\right] =  \\ \left[\forall_{y_{1}, y_{2}, \ldots, y_{n}~|~Q\left(y_{1}, y_{2}, \ldots, y_{n}\right)}~\left(P\left(y_{1}, y_{2}, \ldots, y_{n}\right) \neq \top\right)\right] \end{array} \end{array}\right)
In [5]:
stored_expr.style_options()
no style options
In [6]:
# display the expression information
stored_expr.expr_info()
 core typesub-expressionsexpression
0Lambdaparameters: 1
body: 2
1ExprTuple27, 22
2Operationoperator: 3
operands: 4
3Literal
4ExprTuple5, 6
5Operationoperator: 7
operand: 11
6Operationoperator: 9
operand: 12
7Literal
8ExprTuple11
9Literal
10ExprTuple12
11Lambdaparameters: 19
body: 13
12Lambdaparameters: 28
body: 14
13Conditionalvalue: 15
condition: 16
14Conditionalvalue: 17
condition: 18
15Operationoperator: 27
operands: 19
16Operationoperator: 22
operands: 19
17Operationoperator: 20
operands: 21
18Operationoperator: 22
operands: 28
19ExprTuple23
20Literal
21ExprTuple24, 25
22Variable
23ExprRangelambda_map: 26
start_index: 33
end_index: 34
24Operationoperator: 27
operands: 28
25Literal
26Lambdaparameter: 38
body: 29
27Variable
28ExprTuple30
29IndexedVarvariable: 31
index: 38
30ExprRangelambda_map: 32
start_index: 33
end_index: 34
31Variable
32Lambdaparameter: 38
body: 35
33Literal
34Variable
35IndexedVarvariable: 36
index: 38
36Variable
37ExprTuple38
38Variable