When posting an excerpt of my book on a critiquing site, someone commented on my use of "hahaha" inside the dialogue instead of just having a laughing verb after or before it. They said it took them out of the reading. Obviously, this is subjective, so rather I will ask this:

Which alternative is the most popular and professional? Which do you see the most in writing?

The answers to this question said to use speech tags. But I thought this was bad, and within the phenomenon called filtering. In another question, a user taught me about this, and I've tried to take it to heart.

I thought the alternative was a separate line under, like this.

-That's so funny!

A thundering laugh rolled out of him.

Instead of:

-That's so funny, Mick laughed.

The latter having filtering, in the way there's a "Mick laughed" in between the dialogue and the rest of the text.

So, I thought the alternatives were "hahaha" and having this separate line under. The problem is, which someone once told me, having specification for the dialogue at a later time isn't good, because it often makes the reader have to go back. The person said this in relation to not including name tags after the dialogue, but I believe it applies to the way dialogue is uttered, as in if it is laughed or said normally.

Dialogue quotes are for things a character actually says.

If your character says "hahaha" then fine. But I've never heard anyone do that. You might get a single "ha!" but that's an exclamation not a laugh. Or someone might say "ha ha" (or even "ha ha ha") sarcastically. Again, not a laugh.

If you want to tell your readers that your character laughed then, yeah, you need to just say so. If the laughing comes during the dialogue, you can use a laughing tag. Stylistically, many people recommend against using tags that aren't your basic "said" or "asked" but you can get away with a few.

"It's...I can't even explain it," Griselda laughed.

Or you can describe the action directly.

Griselda laughed. "That's...just wow."

Using the phrase "hahaha" to indicate that someone is laughing is perfectly legitimate in texts, emails, and other informal settings. Don't use it in your writing.

+1 to Cyn, much my answer; use a tag. I can add, I use a single "Ha!" a handful of times in a book. You can also describe the laugh in more detail; Griselda laughed, and covered her mouth as she did for a few seconds. "Oh my god!" I would increase the visual of that, there must be twenty kinds of laughing.

To me this goes for all verbal sound effects; I find it off-putting in novels when an author tries to simulate the sound of screams, moaning (in pleasure or pain), singing, grunting, or inarticulate anger.

Use tags, or just say "Mike grunted." Or describe them, use a metaphor, or an adjective.

You want to immerse your reader in the story hence writing "hahaha" does not give a vivid definition of how the character felt whilst laughing.People read stories to get lost in the moment and feel like they are actually there ,so its the job of the writer to make it so.

*micheal burst out in fits of laughter clutching onto the chair for support.
"That..was..so..funny " he said between laughs. *

this gives the reader a vivid picture of the story as compared to a simple "hahaha"(which can also be interpreted as sarcasm).

I don't see anything wrong in using hahaha as long as it's surrounded with a quote. I mean, I believe a character's style of laughter can be represented by a quoted word like "hahaha" or even "buhahaha". The key pointer here is to surround it by quotes so that the reader knows what's going on.

I don't think 'she laughed' is filtering, and I can't imagine a situation in which it would be. If you read widely you'll see that tagging with 'she laughed' is occasionally fine. It's when too many book-isms stray into the tags that it's annoying. But, having said that it's not a filter, it's still hard for me to imagine someone speaking in a laugh. I'd use the laughter as an action tag, not a dialog tag. This is the difference between:

"I can't believe you just said that," she laughed.

and

She laughed. "I can't believe you just said that.

(very trivial difference, but I'd opt for the second.)

Filtering is when there's an extra (usually two-word) snippet between the viewpoint character and the experience.

She saw her captor approach.

vs.

Her captor approached.

Other filter words and explanation can be found here. i don't think laughter is one of the filters, since it is not an action that leads to an experience, if that makes sense. Laughter is the experience.