# Clarification for "list" in qiime feature-data merge and qiime feature-data merge-seqs
**URL:** https://forum.qiime2.org/t/clarification-for-list-in-qiime-feature-data-merge-and-qiime-feature-data-merge-seqs/5754
**Category:** Ideas and Suggestions
**Created:** [August 24, 2018, 9:57pm UTC](https://forum.qiime2.org/t/clarification-for-list-in-qiime-feature-data-merge-and-qiime-feature-data-merge-seqs/5754 "2018-08-24T21:57:28Z")
**Posts on this page:** 6
**Page:** 1
### Author:  [@Jennifer\_Fouquier](https://forum.qiime2.org/u/Jennifer_Fouquier)
#### Post date: [August 24, 2018, 9:57pm UTC](https://forum.qiime2.org/t/clarification-for-list-in-qiime-feature-data-merge-and-qiime-feature-data-merge-seqs/5754/1 "2018-08-24T21:57:28Z")
In the CLI help docs for `qiime feature-data merge-seqs` (and similar for others I am sure) it says:
` --i-data MULTIPLE ARTIFACT PATH List[FeatureData[Sequence]] The collection of feature sequences to be merged. [required]`
And I think it's a bit unclear.
I have done this several times...I've provided a list of qzas either spaced _or_ in brackets and comma separated because that's a list. π And either way I used the `--i-data` option only once thinking it would know I provided multiple items. I keep forgot to add the option flag multiple times for each item. I think clarification in the CLI would be nice because the word "List" is misleading in a sense.
Just a suggestion, nothing urgent! π
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### Author:  [@thermokarst](https://forum.qiime2.org/u/thermokarst)
#### Post date: [August 24, 2018, 10:31pm UTC](https://forum.qiime2.org/t/clarification-for-list-in-qiime-feature-data-merge-and-qiime-feature-data-merge-seqs/5754/2 "2018-08-24T22:31:14Z")
Hey there @Jennifer_Fouquier --- I agree, it isn't super clear. The reason is because QIIME 2 is _interface agnostic_, so this nomenclature of `List[blah]` business is meant to be applicable irrespective of how any particular interface chooses to implement it (e.g. a GUI might have some kind of multi-select, or drag-and-drop tiles/cards).
Maybe in the case of q2cli we could append the following at the end of the parameter text: `Flag may be specified multiple times.`, or something along those lines. What do you think?
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### Author:  [@Jennifer\_Fouquier](https://forum.qiime2.org/u/Jennifer_Fouquier)
#### Post date: [August 24, 2018, 10:50pm UTC](https://forum.qiime2.org/t/clarification-for-list-in-qiime-feature-data-merge-and-qiime-feature-data-merge-seqs/5754/3 "2018-08-24T22:50:07Z")
Ah, I see.
I think what you suggest would improve things. Although could you say `Flag must be specified multiple times` .... since it's a merge, doesn't that imply you _need_ more than one input?
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### Author:  [@thermokarst](https://forum.qiime2.org/u/thermokarst)
#### Post date: [August 24, 2018, 10:54pm UTC](https://forum.qiime2.org/t/clarification-for-list-in-qiime-feature-data-merge-and-qiime-feature-data-merge-seqs/5754/4 "2018-08-24T22:54:57Z")
> [@Jennifer\_Fouquier](#):
>
> Although could you say `Flag must be specified multiple times` β¦ since itβs a merge, doesnβt that imply you _need_ more than one input?
For this particular example, no, you don't need more than one input --- you can pass just one table to `feature-table merge` and it will be just fine with that (it is effectively a noop).
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### Author:  [@Jennifer\_Fouquier](https://forum.qiime2.org/u/Jennifer_Fouquier)
#### Post date: [March 8, 2020, 6:02am UTC](https://forum.qiime2.org/t/clarification-for-list-in-qiime-feature-data-merge-and-qiime-feature-data-merge-seqs/5754/5 "2020-03-08T06:02:47Z")
@thermokarst, I wrote this up, then realized I already reported this, haha. π€ͺ
I'm looking at `qiime feature-table merge --help` right now and I very strongly recommend that you add something like the following to the `--i-tables` help docs in the CLI. **This clarification should be added to all commands where there is a list.** It's unclear that it should be `--i-tables my-artifact1.qza --i-tables my-artifact2.qza` rather than `--i-tables [my-artifact1.qza, my-artifact2.qza]` or something along those lines which doesn't work. I have done this several times π Maybe it's just me, but this documentation is confusing.
Wherever there is a `List[something]` in the `--help` docs, I suggest adding: `Multiple parameter flags should be used, each with their own input artifact.`
So, for this example:
`The collection of feature tables to be merged. Multiple parameter flags should be used, each with their own input artifact.`
I've messed up on this quite a few times and I am imagining others are because it doesn't read very clear especially if you're used to normal lists like `[item, item, item]`.
Thanks π
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### Author:  [@Negin](https://forum.qiime2.org/u/Negin)
#### Post date: [January 29, 2021, 12:15am UTC](https://forum.qiime2.org/t/clarification-for-list-in-qiime-feature-data-merge-and-qiime-feature-data-merge-seqs/5754/6 "2021-01-29T00:15:22Z")
Totally agreed! It is unclear and I had the same issue.