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Expression of type Lambda

from the theory of proveit.logic.sets.functions.injections

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 A, B, C, Conditional, Lambda, f
from proveit.logic import Forall, InSet, Injections, SubsetEq
In [2]:
# build up the expression from sub-expressions
expr = Lambda([A, B, C], Conditional(Forall(instance_param_or_params = [f], instance_expr = InSet(f, Injections(A, C)), domain = Injections(B, C)), SubsetEq(A, B)))
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, B, C\right) \mapsto \left\{\forall_{f \in \left[B \xrightarrow[]{\text{1-to-1}} C\right]}~\left(f \in \left[A \xrightarrow[]{\text{1-to-1}} C\right]\right) \textrm{ if } A \subseteq B\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
1ExprTuple23, 24, 25
2Conditionalvalue: 3
condition: 4
3Operationoperator: 5
operand: 9
4Operationoperator: 7
operands: 8
5Literal
6ExprTuple9
7Literal
8ExprTuple23, 24
9Lambdaparameter: 18
body: 11
10ExprTuple18
11Conditionalvalue: 12
condition: 13
12Operationoperator: 15
operands: 14
13Operationoperator: 15
operands: 16
14ExprTuple18, 17
15Literal
16ExprTuple18, 19
17Operationoperator: 21
operands: 20
18Variable
19Operationoperator: 21
operands: 22
20ExprTuple23, 25
21Literal
22ExprTuple24, 25
23Variable
24Variable
25Variable