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Comment by scotty79 | Hacker News Reader

> Thus if we forget to use a template processor such as STR, RAW, or FMT then a compile-time error is reported:

    String name = "Joan";
    String info = "My name is \{name}";
    | error: processor missing from template expression

Were literals like "\{" always causing an error?

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Yes, because it's the escape character.

It's the reason they didn't chose "${" like many other languages. Because that's a valid sequence in a string literal.

Which is a nonsensical reasoning they're also requiring a template processor, so string templates were previously impossible in two different ways.

`\{` as an interpolation leader would make sense if untagged string literals became implicit STR templates, but that's not the case.

I guess they want to force you to choose interpolator. So that you won't implicitly use STR when you should have explicitly use SQL.

> I guess they want to force you to choose interpolator.

In which case using `\{}` as the interpolation signal is completely unnecessary, because the new syntax already solves the backward compatibility concerns.

Using just `{x}` like C# and Python, or `$x`/`${x}` like Kotlin, would have sufficed and made the syntax a lot more palatable.

So would using postfix format specifiers, because that printf-style prefix garbage is just gnarly.

\{ protects you from forgetting to use interpolator at all. No other syntax that uses same delimiters as string literal would.

Yes, the escape sequence `\{` is not valid and javac would report an "illegal escape character" error.

Yes. '\' denotes an escape sequence, and "\{" was/is not a valid escape sequence.

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