alt Hacker NewsI'm a HUGE fan of f-strings and I think they should be added to more or less every language in existence. (This is just to show how much I like f-strings, not to be taken literally) `printf`-style format strings seem outdated: why use format strings when I can put my variables IN THE STRING? I want the result of `x+y` to be put {HERE} in this string. Well, just write `"This is here: {x+y} blah"` — it makes perfect sense and immediately lets me see what the resulting strings generally look like.
Basic usage is a no-brainer: write your string, put variables or short expressions in curly braces, add `printf`-style format specifiers after the colon. This is also great because it's a natural extension of `printf`-style format strings.
Of course you can write complicated and confusing f-strings. But then you can write complicated and confusing... anything, really. Many programming languages have extremely weird quirks and cases where basic syntax can be transformed into an unreadable monstrosity, like C syntax for pointers to functions and arrays.
Sure, this increases the language's complexity, but you don't have to use all of it to reap the benefits.
Replies
> why use format strings
Because these are used for locale-specific configuration data. `"This is here: {x+y} blah"` on the other hand isn’t a string (mere data), it’s a program, because you can have arbitrary expressions inside the braces. You don’t want to repeat the `x+y` in each localization file.
I have nothing against ergonomic program constructs for composing strings, but please let’s not confuse such program constructs with mere string literals.
Those aren't the only two options. Like GP I don't like f-strings, but there was something introduced before that: the format function.
It also supports positional with empty {}. And like f-strings, you can put formatting information after a colon.%-based printf-style did also have named variables like this but it seemed less known.