Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Left to Right Programming

graic.net

Post reply on HN
Print view View original

151–160 of 372 posts

Re: Left to Right Programming

#151

Post by dragonwriter »

williamscales wrote: post #26
danielPort9 wrote: post #21

Don’t know why python gets so much love. It’s a painful language as soon as more than one person is involved. What the author describes is just the tip of the iceberg

I find myself writing a very simple style of python that avoids list comprehensions and so on when working in a shared code base. For a language where there is supposed to be only one way to do things, there are an awful lot of ways to do things. Don’t get me wrong, writing a list comprehension can be very satisfying and golf-y But if there should be one way to do things, they do not belong.

> For a language where there is supposed to be only one way to do things

That's not what the Zen says, it says that there should be one -- and preferably only one -- obvious way to do it.

That is, for any given task, it is most important that there is at least one obvious way, but also desirable that there should only be one obvious way, to do it. But there are necessarily going to be multiple ways to do most things, because if there was only one way, most of them for non-trivial tasks would be non-obvious.

The goal of Python was never to be the smallest Turing-complete language, and have no redundancy.

Re: Left to Right Programming

#152

Post by sgarland »

ebonnafoux wrote: post #98
sgarland wrote: post #69

Is the entire complaint that autocomplete doesn’t work well? Have you tried learning your language?

The way people code with Python is by using its large ecosystem, few people only use the standart library. No one knows all the API, the more discoverability there is, the better.

I use stdlib whenever possible specifically because it’s huge, well-tested, and eliminates dependencies.

I don’t know all of its API, but I do read the docs periodically (not all of them, but I try to re-read modules I use a lot, and at least one that I don’t).

Re: Left to Right Programming

#153

Post by mackeye »

disconcision wrote: post #129
kmoser wrote: post #101

Earlier quoted context omitted.

How is it supposed to compile if you've written something syntactically invalid? You can make the argument that the compiler could interpret it in (perhaps even arbitrary) valid way that constitutes a valid syntax, but that's almost worse: rather than being chided with compiler warnings, you now end up with code that compiles but executes indeterminately.

there are approaches to ensure you always or almost always have syntactic validity, e.g. structured editing or error correcting parsing, though of course it's true that the more permissive the system is the more tortured some of the syntactic 'corrections' must be in extreme cases. the approach we're taking with http://hazel.org (which we approximate but don't fully succeed at yet) is: allow normal-ish typing, always…

i saw hazel mentioned forever ago in an eecs 203 lecture and it sent me on a multi-year fp/type theory rabbit hole :) thanks for your work on it!

Re: Left to Right Programming

#154

Post by debazel »

taeric wrote: post #150
jayd16 wrote: post #139

Earlier quoted context omitted.

Seems nonsensical. Column names have no meaning without the table. Table is the object, columns are the properties. What language goes Property.Object? All popular languages have this wrong?

I'm assuming you are largely just not thinking this one through? We are not modeling the domain, we are describing some data we want to select. Without knowing how it is modeled, I can give a brief "top line" for expected select statements on many data models. "I want average_weather, year, zip_code", "I want year, college_name, degree_name, median_graduate_salary, mean_graduate_salary", "..." I don't think it is tou…

How would you even know it's possible get the data before you've chosen a table?

Your example is also not a complete select statement, you would need to go back and add the actual aggregate functions, and oops the zip_code column was actually called zip, so we need to remap that as well. You can almost never finish a select statement before you have inspected the tables, so why not just start there immediately?

Re: Left to Right Programming

#156

Post by taeric »

debazel wrote: post #154
taeric wrote: post #150

Earlier quoted context omitted.

I'm assuming you are largely just not thinking this one through? We are not modeling the domain, we are describing some data we want to select. Without knowing how it is modeled, I can give a brief "top line" for expected select statements on many data models. "I want average_weather, year, zip_code", "I want year, college_name, degree_name, median_graduate_salary, mean_graduate_salary", "..." I don't think it is tou…

How would you even know it's possible get the data before you've chosen a table? Your example is also not a complete select statement, you would need to go back and add the actual aggregate functions, and oops the zip_code column was actually called zip, so we need to remap that as well. You can almost never finish a select statement before you have inspected the tables, so why not just start there immediately?

Often times you don't know it is possible to get some data without consulting the table? Worse, you probably need to consult the views that have been made by any supporting DB team before you go off and build your own rollups. Unless you like not taking advantage of any aggregate jobs that are running nightly for reporting.

And to be clear, I'm all for complaining about the order of a select statement, to a very large degree. It is done in such a way that you have to jump back and forth as you are constructing the full query. That can feel a bit painful.

However, I don't know that it is just the SELECT before FROM that causes this jumping back and forth and fully expect that you would jump around a fair bit even with the FROM first. More, if I am ever reworking a query that the system is running, I treat the SELECT as the contract to the application, not the FROM.

There is a bit of "you should know the database before you can expect to send off a good query", but that really cuts to any side of this debate? How do you know the tables you want so well, but you don't know the columns you are going to ask for?

Re: Left to Right Programming

#157

Post by Naru41 »

I've often thought that if C just had a syntax like Go definding method, C would be much easier to write.

uint16_t (MyStruct* s) some_func() { .. }

uint16_t MyStruct_some_func(MyStruct* s) { .. }

(I guess I should just use C++... but C++ is overwhelmed in many ways)

Re: Left to Right Programming

#158

Post by debazel »

taeric wrote: post #156
debazel wrote: post #154

Earlier quoted context omitted.

How would you even know it's possible get the data before you've chosen a table? Your example is also not a complete select statement, you would need to go back and add the actual aggregate functions, and oops the zip_code column was actually called zip, so we need to remap that as well. You can almost never finish a select statement before you have inspected the tables, so why not just start there immediately?

Often times you don't know it is possible to get some data without consulting the table? Worse, you probably need to consult the views that have been made by any supporting DB team before you go off and build your own rollups. Unless you like not taking advantage of any aggregate jobs that are running nightly for reporting. And to be clear, I'm all for complaining about the order of a select statement, to a very larg…

> How do you know the tables you want so well, but you don't know the columns you are going to ask for?

Simply because there are a lot more columns than there are tables.

Of course, I sometimes forget the exact table name as well. However, this is mostly not an issue as the IDE knows all table names before anything has been entered. By simply entering `FROM user`, the autocomplete will list all tables that contain `user`, and I can complete it from there. I cannot do the same with the column selection unless I first write the FROM part. And even if I do know exactly which columns and tables I want I would still want autocomplete to work when creating the SELECT statement. Rather than typing `zip_code`, I can most likely just type `z`.

That is why 99% of my select queries start as `SELECT * FROM mytable`, and then I go back to fill in the select statement. And it's not just me, all colleagues I've worked with does exact same thing.

For larger, more complicated queries, you'll have to go back and forth a lot as you join tables together, that is unavoidable, but 80-90% of my queries could be finished in one go if the FROM part came first.

Re: Left to Right Programming

#159

Post by jayd16 »

taeric wrote: post #148
jayd16 wrote: post #142

Earlier quoted context omitted.

This assumes I have all the column memorized but not all the tables? Even in your example, first and last could refer to student or teacher. But presumably you know you're looking for student data before knowing the exact columns.

No, this assumes you know what you want for a query. Which, seems largely fair? Like, how would you send this question to someone? Or how would you expect it to be sent to you? If your boss doesn't tell you from what table they want some data, do you just not answer? And sure, there could be ambiguities here. But these are not really fixed by listing the sources first? You would almost certainly need to augment the s…

If my boss asks me for a zip code, I'm going to ask "for what?"

If they ask for "address for a customer" I can go to the customer table and look up what FKs are relevant and collect all possible data and then narrow down from there.

Re: Left to Right Programming

#160

Post by michaelfeathers »

bear8642 wrote: post #131
michaelfeathers wrote: post #124

This is called point-free style in Haskell. Sometimes it is called a fluent-interface in other languages.

> Sometimes it is called a fluent-interface in other languages. Where've you heard it called that? I've normally heard tacit programming

The developers of JMock, the original library for Java.
Post reply on HN