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Expression of type Lambda

from the theory of proveit.core_expr_types.conditionals

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 Conditional, Lambda, a
from proveit.core_expr_types import Q_1_to_m
from proveit.logic import And, Equals, TRUE
In [2]:
# build up the expression from sub-expressions
sub_expr1 = And(Q_1_to_m)
expr = Lambda([a, Q_1_to_m], Equals(Conditional(a, And(sub_expr1, TRUE)), Conditional(a, sub_expr1)).with_wrapping_at(1))
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, Q_{1}, Q_{2}, \ldots, Q_{m}\right) \mapsto \left(\begin{array}{c} \begin{array}{l} \left\{a \textrm{ if } Q_{1} \land  Q_{2} \land  \ldots \land  Q_{m} ,  \top\right.. \\  = \left\{a \textrm{ if } Q_{1} \land  Q_{2} \land  \ldots \land  Q_{m}\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
1ExprTuple8, 14
2Operationoperator: 3
operands: 4
3Literal
4ExprTuple5, 6
5Conditionalvalue: 8
condition: 7
6Conditionalvalue: 8
condition: 10
7Operationoperator: 12
operands: 9
8Variable
9ExprTuple10, 11
10Operationoperator: 12
operands: 13
11Literal
12Literal
13ExprTuple14
14ExprRangelambda_map: 15
start_index: 16
end_index: 17
15Lambdaparameter: 21
body: 18
16Literal
17Variable
18IndexedVarvariable: 19
index: 21
19Variable
20ExprTuple21
21Variable