Add EIP-5875: Instruction to Get Transaction Index of Block

[xinbenlv]

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[eth-bot]

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(fail) eip-5875.md

classification
newEIPFile

• File with name EIPS/eip-5875.md is new and new files must be reviewed
• This PR requires review from one of [@lightclient, @axic, @gcolvin, @SamWilsn]

[frangio]

Previously discussed in #222.

[Pandapip1]

Initial review. There's a lot to like!

[xinbenlv]

Thank you @Pandapip1 , all suggestions commited. Ready to merge

[lightclient]

Also discussed here: #4363

[lightclient]

Generally:

• s/tx number/transaction index/g
• There are real implications of this in block production that need to be explored in the rationale and security considerations. For starters, how will this affect mev?

[lightclient]

This is unnecessary.

[xinbenlv]

Sure, I could remove it.

QQ: If we don't make OPCODE a placeholder number, how do we allow people to propose EIPs picking arbitrary unused new opcodes without conflicting with other drafts, knowing some of such core EIPs are taking long / never going to be adopted?

[lightclient]

You don't specify how much the operation costs.

[xinbenlv]

Good point. Added now. Thank you!

[lightclient]

I don't understand this sentence. Did you mean word length? In that case I would just omit this because the word length is not decidable by an instruction.

[xinbenlv]

I was referring to the bounding. Updated the sentence and could you check if it reads better now?

[Pandapip1]

Suggested change

	4. Further discussion is needed about potentially bounding the transaction index for simpler on-chain computation if use case arises.
	5. Further discussion is needed about whether to use transaction index within the block or globally. Globally makes it easier to compute number distance between two transactions directly but is useless for DAG
	if we foresee a DAG future.
	- Further discussion is needed about potentially bounding the transaction index for simpler on-chain computation if use case arises.
	- Further discussion is needed about whether to use transaction index within the block or globally. Globally makes it easier to compute number distance between two transactions directly but is useless for DAG
	if we foresee a DAG future.

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[github-actions]

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[Dawidowak]

Ok