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Left to Right Programming

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Re: Left to Right Programming

#311

Post by stonemetal12 »

sgarland wrote: post #79
juancn wrote: post #39

SQL shows it's age by having exactly the same problem. Queries should start by the `FROM` clause, that way which entities are involved can be quickly resolved and a smart editor can aid you in writing a sensible query faster. The order should be FROM -> SELECT -> WHERE, since SELECT commonly gives names to columns, which WHERE will reference. You could even avoid crap like `SELECT * FROM table`, and just write `FROM…

It's written that way because it stems from relational algebra, in which the projection is typically (always?) written first. >The order should be FROM -> SELECT -> WHERE, since SELECT commonly gives names to columns, which WHERE will reference. Per the SQL standard, you can't use column aliases in WHERE clauses, because the selection (again, relational algebra) occurs before the projection. > You could even avoid cr…

>Per the SQL standard, you can't use column aliases in WHERE clauses, because the selection (again, relational algebra) occurs before the projection.

Don't blame the math for sloppy implementation. Nothing in the math suggest where aliases should be specified. Don't get me wrong it is a coinvent, logical place to put them, but as you say it rather limits their use, and could have been done better.

Re: Left to Right Programming

#312

Post by andyferris »

cesarb wrote: post #293
sriku wrote: post #199

This is almost FP vs OOP religious war in disguise. Similar to vim-vs-emacs ... where op comes first in vim but selection comes first in emacs. If you design something to "read like English", you'll likely get verb-first structure - as embodied in Lisp/Scheme. Other languages like German, Tamil use verbs at the end, which aligns well with OOP-like "noun first" syntax. (It is "water drink" word for word in Tamil but "…

> Other languages like German, Tamil use verbs at the end Doesn't German have the main verb on the second position? (For a simple example, "I drink water" would be "Ich trinke Wasser")

Yeah I thought the German ambiguity was SVO vs OVS, “Fritz fished fish” vs “Fish, fished Fritz”..

Re: Left to Right Programming

#313

Post by 9rx »

sgarland wrote: post #304
9rx wrote: post #218

Earlier quoted context omitted.

Interestingly, the inventor of relational algebra for database management put the "FROM" first in his query language: https://dl.acm.org/doi/pdf/10.1145/1734714.1734718

What section did you see this? I see GET (i.e. SELECT) first.

Section 3.3. "SELECT" only comes first if you omit "FROM". In SQL, if it allowed, that would be something like: `SELECT table.column`.

Re: Left to Right Programming

#314

Post by sgarland »

marzell wrote: post #301
sgarland wrote: post #79

Earlier quoted context omitted.

It's written that way because it stems from relational algebra, in which the projection is typically (always?) written first. >The order should be FROM -> SELECT -> WHERE, since SELECT commonly gives names to columns, which WHERE will reference. Per the SQL standard, you can't use column aliases in WHERE clauses, because the selection (again, relational algebra) occurs before the projection. > You could even avoid cr…

> Per the SQL standard, you can't use column aliases in WHERE clauses, because the selection (again, relational algebra) occurs before the projection. Except this works in most major vendor SQL implementations. And they all support relation aliases in SELECT... Seems the standards have long fell behind actual implementations.

To clarify, I mean you can’t do this:

    SELECT id AS foo
    FROM MyTable
    WHERE foo = 1;
Similarly, you can’t do this:

    SELECT id
    FROM MyTable
    WHERE id = MAX(id);
Because in both cases, when the WHERE predicate is being executed, the engine doesn’t yet know what you’re asking it to find - for the former, SELECT hasn’t yet been called, so the alias isn’t applied; for the latter, the aggregation happens after filtering, so it can’t know what that maximum value is.

You can of course alias columns for SELECT however you’d like, and can also use those aliases in ORDER BY. You can also trivially refactor the above examples to use subqueries or CTEs to accomplish the goal.

Re: Left to Right Programming

#315

Post by saghm »

This is a view I've expressed for years now, and usually people are pretty repetitive to it until I follow it up with "and that's a big part of why I find Ruby easier for me to write scripts in than Python". As someone who has never really worked much on production code in either of those languages, I'll never understand how Python managed to end up in the situation where it's installed enough to be the scripting language of choice when people want to reach for something other than bash. Sure, Ruby has its warts, but it's not like people are really delving into the messy parts of Python either for their scripts, and at least Ruby hasn't had a debacle major version breaking changes in the last decade.

Re: Left to Right Programming

#316

Post by pech0rin »

I guess I’m so old that I remember time without autocomplete. Where programmers just knew what functions existed and how to use them. Usually by looking them up in a manual and then -gasp- remembering them. Languages shouldn’t be optimized for laziness or not using your brain.

“Shut up old man” yes yes okay.

Re: Left to Right Programming

#317

Post by Pxtl »

IshKebab wrote: post #286
Pxtl wrote: post #279

Earlier quoted context omitted.

I've pretty much embraced PowerShell for scripting. The language is warty as hell and seems to be entirely made of sharp edges but I've gotten used to it and it does have a lot of excellent ideas.

Yeah I'm toying with nushell which is like Powershell but with a less offensive syntax. But when I say "scripting" I don't mean shell scripting. I mean stuff like complex custom build systems or data processing pipelines. I would never do those in any shell language.

Actually while I use it heavily for shell scripting, it's also also my go-to for python-style scripting too. Mostly because it's the one I'm most familiar with because of professionally doing DevOps on an MS stack with a lot of legacy stuff, but still:

It's just object-y enough to be excellent at filtering and shunting and translating records from API endpoints to CSV files to SQL data rows, etc. I'm not sure I'd recommend it to anybody to pick up because of all the sharp ends (eg it uses Javascript falseyness except SQL NULL has the ADO.Net "DBNull" which isn't falsey) but because I'm so familiar with it I find it quite good at that stuff.

As much as people bag on the syntax (like the operators all starting with hyphen, and all the .NET functions speak with an accent), the real problem is how many edge-cases are in there, like strange behaviors of the error stream, overcomplicated scope rules, FileSystem providers for the registry and SQL server and other objects no reasonable person would ever want to use as a "file", empty-array objects getting silently converted into null, etc.

Re: Left to Right Programming

#318

Post by stonemetal12 »

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 love python, as long as were are talking about small teams, short, and short lived programs. The lack of static types makes things quick to implement even if it isn't too sound, and the strong typing keeps you from fucking up too badly. That is why I think it gets so much love in data science, it is great for noodling around while you are trying to figure something out.

On the other hand if you are going to be building something that is going to be long lived, with multiple different teams supporting it over time, and\or larger programs where it all doesn't fit in (human) memory, well then python is going to bite you in the ass.

There isn't a one size fits all programming language, you need at least two. A "soft" language that stays out of your way and lets you figure things out, and a "hard" language that forces the details to be right for long term stability and support.

Re: Left to Right Programming

#319

Post by aredox »

sriku wrote: post #199

This is almost FP vs OOP religious war in disguise. Similar to vim-vs-emacs ... where op comes first in vim but selection comes first in emacs. If you design something to "read like English", you'll likely get verb-first structure - as embodied in Lisp/Scheme. Other languages like German, Tamil use verbs at the end, which aligns well with OOP-like "noun first" syntax. (It is "water drink" word for word in Tamil but "…

>where op comes first in vim

Doesn't Kakoune reverses that, and it makes so much more sense?

https://kakoune.org/why-kakoune/why-kakoune.html

Re: Left to Right Programming

#320

Post by aredox »

cesarb wrote: post #293
sriku wrote: post #199

This is almost FP vs OOP religious war in disguise. Similar to vim-vs-emacs ... where op comes first in vim but selection comes first in emacs. If you design something to "read like English", you'll likely get verb-first structure - as embodied in Lisp/Scheme. Other languages like German, Tamil use verbs at the end, which aligns well with OOP-like "noun first" syntax. (It is "water drink" word for word in Tamil but "…

> Other languages like German, Tamil use verbs at the end Doesn't German have the main verb on the second position? (For a simple example, "I drink water" would be "Ich trinke Wasser")

Yeah, wrong one, but there are many languages out there where the verb is always at the end (Latin, Japanese I think).
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