Code is heuristically unreachable

Question

What does this mean in contrast to "unreachable code detected"?

Does resharper actually say that? – sehe Apr 03 '11 at 21:06 — sehe, Apr 03 '11 at 21:06
Yeah it does say that, I've seen it get it wrong though – JeremyWeir Apr 03 '11 at 21:08 — JeremyWeir, Apr 03 '11 at 21:08

score 58 · Accepted Answer · answered Apr 03 '11 at 21:07

58

Heuristically unreachable means possibly unreachable code. Unreachable code is certainly unreachable.

answered Apr 03 '11 at 21:07

Adrian Marinica

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I'm finding this cropping up when it's impossible for me or ReSharper to know whether something is always going to be false (or `== null`). – Nick Bedford Nov 02 '11 at 01:23
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Sometimes an object is just never going to be null (or ReSharper thinks that is the case) IQueryable object pulling data when say you know that the query is not going to pull any records, it still is not going to be "null" Just have to refactor your code to not make ReSharper unhappy as it is correct possibly a larger % of the time over most developers. – Tom Stickel Oct 22 '15 at 05:09

score 8 · Answer 2 · edited Mar 24 '21 at 06:05

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Here's an example of ReSharper giving the cryptic "Heuristically unreachable code" warning:

It's an example of:

ReSharper being way too smart for itself, because if you remove it the compiler will complain about a lack of a return statement
Use of a word that is not common lexicon

edited Mar 24 '21 at 06:05

Pang

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answered Nov 01 '18 at 23:27

Ben Power

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score 1 · Answer 3 · answered Aug 28 '14 at 22:35

Say you're deleting 2 different kinds of objects in a unit test and you want to use a try/catch for both types.

If you delete one, and then check to see if it was successful without properly casting using:

Assert.IsNull(obj1);

The "IsNull" may always be null because you casted obj1 incorrectly, or did something above the greyed out code incorrectly with obj1, the next try/catch will be greyed out.

Try fixing the thing you're trying to Assert.IsNull and once it's not always null or undefined, the greyed out code will be reachable.

Code is heuristically unreachable

3 Answers3

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