Standardize __repr__ for sheets and columns

[cool-RR]

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I find the current __repr__ for sheets confusing:

In [1]: vd.sheet
Out[1]: 2023-10-21-14-21-50-423073

It's not clear enough it's a sheet. I don't want to have to do type(x) to figure out what something is.

Here's how it looks like after this change:

In [1]: vd.sheet
Out[1]: <DirSheet: 2023-10-21-14-21-50-423073>

In [2]: vd.sheet.columns
Out[2]:
[<Column: directory>,
 <Column: filename>,
 <Column: abspath>,
 <Column: ext>,
 <Column: size>,
 <Column: modtime>,
 <Column: owner>,
 <Column: group>,
 <Column: mode>,
 <Column: filetype>]

[cool-RR]

I assume the CI failure is not related to my change.

[anjakefala]

Hey @cool-RR, could you give me examples of times when you would have found this change valuable? Especially the tagging that columns are a Column? It's an interesting proposal, but I'm trying to assess if we would also like it.

Before we could merge this in, we would definitely need to have a __str__, with the previous __repr__ text! A grep shows a bundle of places with something like basepath = str(self.source)

[cool-RR]

Hey @cool-RR, could you give me examples of times when you would have found this change valuable?

When I'm developing my scripts, I snoop around a live VisiData session to look at the different objects and how they relate to each other. When I see an object is just 2023-10-21-14-21-50-423073 I have to do an additional type() call to confirm that it's a sheet.

Especially the tagging that columns are a Column?

Columns are already tagged as columns. Currently their __repr__ shows up as Column:directory. I'm just making it look more standard, which is <Column: directory>. It could be argued that the colon should be dropped, or that there should be a colon but no space, or that there should be a comma instead. The pointy brackets however are important in my opinion, to make the boundaries from other objects clear.

Here's the similar representation for some built-in Python objects:

<sqlite3.Connection object at 0x7f3a20ca6c70>
<re.Match object; span=(0, 1), match='f'>
<_MainThread(MainThread, started 139858874212352)>

It's an interesting proposal, but I'm trying to assess if we would also like it.

Before we could merge this in, we would definitely need to have a __str__, with the previous __repr__ text! A grep shows a bundle of places with something like basepath = str(self.source)

Added, though I thought self.source points at something different than a sheet or a column.

[saulpw]

I thought self.source points at something different than a sheet or a column.

It can be either a Path (for a source sheet), or another Sheet (for a derived sheet or meta-sheet).

[saulpw]

Okay, thanks @cool-RR!