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std/encoding/csv.ts - `stringify` could use improvement and better documentation
stringify in std/encoding/csv.ts takes a lot of reading to figure it out. After looking over the documentation and source code, I've discovered that I need to provide objects then specify what each column is along with how each column should access a property on the objects.
Some suggestions:
- Unfortunately the property access is not type safe and so it's possible to change a property name and break this code without being notified. The API could be improved if it were type safe between the property names and the objects being provided as this would prevent bugs.
- It would be nice if there were something analogous to
JSON.stringify(data)here, where I can just havedatain memory beingstring[][]and then dostringify(data)and get the result. I don't want to bother having to specify column names and property names on an object. - It might be easier to understand if there were some examples, but I think examples wouldn't be required if it wasn't so complex.
By the way, a simple API I've found for csv parsing and stringifying is https://www.npmjs.com/package/csv-string -- I almost feel like the csv parsing in std should be really simple then people can map the data in and out to objects if they feel like. There's a lot going on right now in there.
About number 2, I think that the best solution would be to move the columns argument into the options object, this way the user could specify which columns he wants in the output and if no option is provided, then all columns will de present into the output.
About 1, would be the case to think about adding a generic parameter to stringify to specify the type of the input object or am I wrong? I didn't fully understand the type safety that this funciton would have, can you clarify it for me?
And about 3, I think that the examples would do a good job, but I'll take a deep look at the code you provided as a simple solution and see if it fits into the case.
I took a quick look at it already and at least for me the deno implementation looks simpler, but would benefit from a better documentation.
I took a deeper look at the csv-string implementation and it really looks simpler. I still stand with the idea of passing columns through the options object though which it would add some complexity to deno's implementation. What do you guys think? @bartlomieju @crowlKats @dsherret
Columns in json objects don’t guarantee order. I would assume an array of arrays is the only way to maintain column order or possibly a “Map” interface that does retain order in keys.
I didn't specifically thought about order, but your suggestion is good. But in this case a normal array wouldn't do the job? Why a array of arrays? Didn't manage to think this through
Arrays will maintain order. You would just need to add a header array first. So first array is first row and that contains an array of columns.
You’ll need to add empty spaces for missing cells.
I think. Map might be better suited here
Nice, I got the idea, thanks for your suggestions! I'll make a PR this week with the modifications
