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Comment by wund3rb4r88 | Hacker News Reader

So what reason is there for adding a new string formatting syntax that looks nothing like string formatting syntax used in any other language, and obliges a non-insignificant userbase to adapt?

Technological purity or scratching some philosophical itch would be a poor reason, IMO, given how broad the externalized costs run.

So is it provably easier to reason around the new style? Reduce computing time by an order of magnitude (in the modern era where compute cycles and memory are hella cheap)?

Code is to be written so it’s understandable and useful for humans first, right?

How does a third syntax for a solved usecase offer real value to the user base?

Or are we just being sycophants of so-called experts, peddling some novel “look”. Experts who largely built a rep on first mover advantage, but have since seen that excuse for being deified evaporate as the rest of world learned all the same tricks?

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>that looks nothing like string formatting syntax used in any other language

PHP echo "There are $apples apples and $bananas bananas.";

Ruby puts "I have #{apples} apples"

TCL puts "I have $apples apples."

Typescript console.log(`I have ${apples} apples`);

Python print(f"I have {apples} apples")

Looks pretty similar to me, and if you like understand-ability by humans so much I think f-strings win hands down. But if you disagree, there's plenty of code out there still using % strings or .format() and they're not going anywhere any time soon.

Python's string format is also very similar to the "double mustache" convention widely used in web development. The following template string:

    "I have {{apples}} apples"

To my certain knowledge this works in Jinja2, Django templates, Vue.js, mustache.js, handlebars.js, and probably many others.

PEP 498 mentions that they did look at other languages to see what was supported:

https://www.python.org/dev/peps/pep-0498/#similar-support-in...

And they link to this Wikipedia article, which lists many examples:

https://en.wikipedia.org/wiki/String_interpolation

Scanning through that, my impression is that "there is nothing new under the sun" and aside from an occasional "$" or "#" prefix, or a willfully arbitrary deviation like ColdFusion, the conventions can all be traced the Bourne shell /bin/sh/ which was released in 1979. Prior to that, the prinf() syntax was presumably the most common, but it's obscure.

Does anyone know if the ${variable} convention was original with the Bourne shell, or if it can be traced back further?

I am surprised to find that the 6th edition shell had only $1 etc positional parameter expansion, and named shell variables are not described in its man page

http://man.cat-v.org/unix-6th/1/sh

Anecdotally, the only language in that list I encounter anymore is Python. TypeScript is a closest second.

I’m rather done with this interpreted, dynamic typed, language and the hell holes they dig us into.

DRY could be applied to more contexts than code logic: stop rewriting language features unless there is more than a subjective win of “looks nicer.” or performance is improved by an order of magnitude.

The conversations the Python community should be having are not “once again we must discuss and consider a solution to a solved problem.”

When that’s the sort of progress the language devs are prioritizing, it’s a sign to me they’re out of ideas or incapable of fixing the bigger flaws.

Could you please stop creating accounts for every few comments you post? We ban accounts that do that. This is in the site guidelines: https://news.ycombinator.com/newsguidelines.html.

HN is a community. Users needn't use their real name, but should have some identity for others to relate to. Otherwise we may as well have no usernames and no community, and that would be a different kind of forum. There are legit uses for throwaways, just not routinely.

Lots more explanation: https://hn.algolia.com/?sort=byDate&dateRange=all&type=comme...

Python string interpolation uses the same syntax as str.format(), and happens to be shared by c#’s string interpolation

> So what reason is there for adding a new string formatting syntax that looks nothing like string formatting syntax used in any other language

The new syntax is more like other modern languages, not less.

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