How to replace==in the equation with ->?

Question

It is required to replace the ==

in equation

2b==E ^ x0- x0

with ->,

becoming:

2b ->E ^ x0- x0

My personal attempt was like this, but it didn't achieve the goal

eq1 = E^x0 - x0 - 2 b == 0
eq2 = eq1 /. k_ + m_ - 2 b == 0 :> 2 b == k + m
eq3 = eq2 /. Thread["==" -> "->"]

Answer 1

A few observations

eq = 2 b == E^x0 - x0;

The Head of eq is Equal

Head @ eq

Equal

The Head is always at position 0

ps = Position[Equal] @ eq

{{0}}

Therefore we must ReplaceAt position 0

ReplaceAt[eq, _ :> Rule, ps]

2*b -> E^x0 - x0

or use ReplaceAll like Syed suggested in his commentary.

We can also use ToRules:

First @ ToRules @ eq

2*b -> E^x0 - x0

or Apply with its third argument:

Apply[Rule, eq, {0}]

2*b -> E^x0 - x0

Addendum

Like lericr mentioned in his comment, Apply doesn't need the third argument in this case and can also be written as:

Apply[Rule, eq];

or

Apply[Rule] @ eq

or

Rule @@ eq