nit: missing a couple backticks between `a_top` and `0`

Maybe we shoud "otherwise end the script with success" so that we can softfork in new data?

I think it might be simpler to not name these since they aren't really "opcodes" now.

```suggestion - Pop the stack as minimal `CScriptNum` as `n`. The implementation is exactly the same as `OP_INSPECTINPUT`, but uses the current input instead of reading the input from stack. The names of the `OP_INSPECTINPUTx` would be replaced by `OP_INSPECTCURRENTINPUTx` ```

```suggestion 1. **Streaming Opcodes for streaming hashes**: There is an existing MAX_SCRIPT_ELEMENT_SIZE is 520 bytes, that is the maximum message size that OP_SHA256 can operate on. This allows hashing on more than 520 bytes while still preserving the existing security against resource exhaustion attacks. The proposal for this is still under discussion in https://github.com/ElementsProject/elements/pull/817. We suggest the latest scheme suggested by Russel O'Connor ```

should be "do not error if" rather than "is" ?

should be `OP_PUSH256NUM_1`

Can be substituted with `OP_INSPECTINPUTINDEX OP_INSPECTINPUTx`, is it worth it to add 9 opcodes to save 2 bytes ?

What is the context when hash algorithms besides SHA256 would be needed ?

"Pop" used twice