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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 InSet, Injections
In [2]:
# build up the expression from sub-expressions
expr = Lambda(f, Conditional(InSet(f, Injections(A, C)), InSet(f, Injections(B, C))))
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())
f \mapsto \left\{f \in \left[A \xrightarrow[]{\text{1-to-1}} C\right] \textrm{ if } f \in \left[B \xrightarrow[]{\text{1-to-1}} C\right]\right..
In [5]:
stored_expr.style_options()
no style options
In [6]:
# display the expression information
stored_expr.expr_info()
 core typesub-expressionsexpression
0Lambdaparameter: 9
body: 2
1ExprTuple9
2Conditionalvalue: 3
condition: 4
3Operationoperator: 6
operands: 5
4Operationoperator: 6
operands: 7
5ExprTuple9, 8
6Literal
7ExprTuple9, 10
8Operationoperator: 12
operands: 11
9Variable
10Operationoperator: 12
operands: 13
11ExprTuple14, 16
12Literal
13ExprTuple15, 16
14Variable
15Variable
16Variable