Could you consider removing the semicolons at the end of the lines

[gitchc]

Could you consider removing the semicolons at the end of the lines or make them optional?
While adding semicolons can make the code appear more rigorous, for a scripting language, ease of use might be more important. Like Python or JavaScript do not require them. hope you can take this into consideration

[gitchc]

Or consider making it a parameter that can be freely chosen, so that scripts written in other languages can switch over at a relatively low cost

[schungx]

JavaScript's semicolon omission is known to cause very subtle bugs and is generally considered a bad idea.

Python I believe is line-based so that a line break sort of acts as a semicolon?

Rhai is not line-based so it continues to the next line, there must be a deterministic way for the parser to decide whether it is the end of the statement, or the next token is part of the current statement.

A typical scenario:

let a = foo; +b

let a = foo
+b

[gitchc]

What I actually want to express is that omitting semicolons can make scripts more user-friendly, although it might also introduce some minor issues. Like JavaScript and Python, also like Groovy. There seems to be an tacit agreement that diminishes the importance of semicolons. Regarding the issue you mentioned earlier, if parsing is done on a line-based; and if there is a start with ([{, it might be possible to treat the related code as a single line by closing it appropriately, maybe a solution. Just a suggestion

[Crazy-Bunny]

As we know, languages like Python, Shell, etc., typically don't require semicolons at the end of statements, and in JavaScript, semicolons are also optional. RhaiScript as a scripting language, adhere to the same guideline and provide semicolons as an optional feature to developers? This would greatly help in replacing our existing projects with RhaiScript

[schungx]

Well, whitespace-significant languages like Python use whitespace to provide structure so a line break acts as a form of statement delimiter.

C-type languages are not whitespace significant and so they form blocks with braces, instead of indentation like Python. Rhai is a C-style language (so is Java, C#, Rust, Go etc).

These two styles are quite different... Would you be content to have no semicolons but requiring braces to form blocks?

Because the way of defining blocks for both styles are different.

I believe it would be relatively easy to provide a no-semicolon option, but very difficult to avoid braces to delimit blocks. I can, though, change it to begin and end.

[AngelicosPhosphoros]

As for myself, required semicolons is one of the reasons to choose this language.

[schungx]

OK, closing this for now as off-topic, since Rhai is a C-style language.

[philocalyst]

Hi! I think it's silly to limit your language off of the arbitrary, ill-defined concept of "C-style" language. I mean, it's modeled after Rust, which is some kind of famous for being a low-level language that redefines the most of C's paradigms.

A good example is what pushed me to say something, Swift. Which has no semi-colons, has a core design goal of tight integration with C-like systems! And this is a new language, built many years of digesting Javascripts semicolons, which are apparently "generally considered a bad idea" -- not by one of the most academically inclined language teams I guess?

Personally, despite coding many thousands of lines of Rust and other languages with semi-colons, I find it still to be a distracting piece of visual noise, especially because they, semantically, generally serve no purpose and therefore are easy to leave out when conceptualizing a solution. I think scripting languages are entirely designed for this conceptualization stage, and any "subtle bugs" that result out of a lack of a semi-colons should be considered as normal pitfalls of any other syntax option or keyword; that is, something to work around.

If you know of any place I could contribute to a semi-colon-less mode, let me know! Building a larger project around this language and would really prefer my scripts to not have semi-colons. Appreciative of the language, and I hope this doesn't come off as spiteful, just find this something that shouldn't be so easily discounted. Happy to discuss further and bring contributing sources if that would help :)

[schungx]

Thanks for your candid comments. Let's reopen this.

I'm not adverse to a semicolon-less mode per se but just that it might be a tad difficult to implement within the current code framework.

That doesn't mean it is not possible.

Currently Rhai uses a lexer to convert a characters stream into tokens at low level. The tokenizer essentially ignores whitespace and newlines.

To get rid of semicolons we'll need to support indentation structuring, which means tracking the indentation level of code and detecting newlines as well as the indentation of the next line.

I have thought about this and I think we can make the lexer more intelligent to detect indention structure and then return the necessary tokens (like { when indenting and } when outdenting, ; for newlines when it is at the end of a statement).

The lexer currently has a ControlBlock which is interior mutable to keep track of out-of-context state such as strings interpolation. Maybe state regarding the indentation structure can also be kept. It allows the parser to tell the lexer whether it is currently at a position where the end of a statement is valid, for example.

Then the parsing errors will need to be adjusted so they spit out the correct info in semicolon-less mode.