Ok so im making a character for 4-shot, we are starting at level 6. im considering 5 levels of warlock and 1 of fighter. the warlock would be a Hexblade with pack of the blade, the invocations thirsting blade and improved pact weapon. The fighter level would be for thrown weapons fighting style. So could I  have a dagger as a pact weapon, thrown it once, dismiss it and have to reappear in my hand to throw again as part of the thirsting blade allowing 2 attacks?

I believe it takes an action to summon your pact weapon. So you can throw it then dismiss it but would have to use your action next turn to use it again

Pact of the Blade

 

You can use your action to create a pact weapon in your empty hand. You can choose the form that this melee weapon takes each time you create it (see the Weapons section for weapon options). You are proficient with it while you wield it. This weapon counts as magical for the purpose of overcoming resistance and immunity to nonmagical attacks and damage.

Your pact weapon disappears if it is more than 5 feet away from you for 1 minute or more. It also disappears if you use this feature again, if you dismiss the weapon (no action required), or if you die.

Would that be a Hexblighter? But no, I don't think it would. Thrown Weapon lets you draw the weapon for no action, it doesn't say anything about magically summoning or creating a new one (which does say it costs an action).

At level 3 a fighter can take Eldritch Knight, which lets them bond with a weapon and recall it as a bonus action if thrown. So you could attack/bonus-action-recall/attack that way. But you'd have to go 3/3 on levels and I think you'd lose access to Improved Pact Weapon that way until later. 

Edit: Nope, it's Thirsting Blade you'd lose, so that wouldn't work yet either. 

So of there not a difference between creating a pact weapon and summoning it from the holding plan it’s shunted to when dismissed?

No. The shunting only happens if it's a magic dagger that you've performed a 1 hour ceremony on, otherwise it's just a new vanilla dagger every time. But talk to your DM, see if he's cool with it? Daggers don't do that much damage, so you're probably not unbalancing anything that way. Although if it's a magic weapon already, then Improved Pact Weapon won't help much...

Why do you want to throw things though? You've got two beams of Eldritch Blast, for 1d10 + CHA each, at lvl 5 if you took agonizing blast which is pretty mean for a range attack. Maybe make a big sword with your pact blade and chop up anything dumb enough to get close? 

18 CHA with 5 warlock and 1 fighter the dagger does 1d4+7. EB is so overused, I want to plat a warlock that does something different. If I was gonna do EB as a prime damage source Id do 2 warlock and 4 sorcerer and go classic sorlock. 

The point is that the dagger would be my hex weapon and also the pact weapon. The plan was to throw the hex and pact dagger, shunt to holding plane, recall and throw again with the thirsting blade invocation. thinking on it more I do see the issue, it wont work, so im probably gonna scrap the idea and do something else. 

May I offer a Plan B?

Go 5 levels Artificer (Battle Smith) + 1 Level Fighter (For Thrown Weapon Fighting)

Get Returning Weapon Infusion.

Profit :D

That works for the combat side but the character concept, background and personality would not fit an artificer. But again thanks for the help guys. Ill figure out another concept, its all good

I agree, ask your DM.  There are certain ways this could be abused, but if it is for cool RP effect I think most DM's would be fine with the Dagger summoning... especially for a limited 4 session run.