# from the theory of proveit.logic.equality¶

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.
# import Expression classes needed to build the expression
from proveit import Conditional, ExprTuple, Lambda, a, b, c, d
from proveit.logic import And, Equals
In [2]:
# build up the expression from sub-expressions
expr = ExprTuple(Lambda([a, b, c, d], Conditional(Equals(a, d), And(Equals(a, b), Equals(b, c), Equals(c, d)))))
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(\left(a, b, c, d\right) \mapsto \left\{a = d \textrm{ if } a = b ,  b = c ,  c = d\right..\right)
In [5]:
stored_expr.style_options()
no style options
In [6]:
# display the expression information
stored_expr.expr_info()
core typesub-expressionsexpression
0ExprTuple1
1Lambdaparameters: 2
body: 3
2ExprTuple16, 17, 18, 19
3Conditionalvalue: 4
condition: 5
4Operationoperator: 14
operands: 6
5Operationoperator: 7
operands: 8
6ExprTuple16, 19
7Literal
8ExprTuple9, 10, 11
9Operationoperator: 14
operands: 12
10Operationoperator: 14
operands: 13
11Operationoperator: 14
operands: 15
12ExprTuple16, 17
13ExprTuple17, 18
14Literal
15ExprTuple18, 19
16Variable
17Variable
18Variable
19Variable