Semicolon?

[John Colvin]

On Wednesday, 31 March 2021 at 21:51:07 UTC, Arun wrote:
> Just curious. Does the compiler need semicolon anymore? Are 
> there corner cases that don't work without semicolon?

SIL (in-house language @ Symmetry Investments, implemented in D) 
has optional semi-colons. We made them work by insisting that 
statements are unambiguous between eager and non-eager parsing 
over line-breaks. Instead of choosing which version is correct 
with a rule, we simply disallow anything that would be ambiguous.

For example:

```
a = foo
(bar())
```

Instead of deciding which interpretation is correct (assign the 
function `foo` to `a` then call `bar` *or* call `bar`, pass 
result to `foo`, assign result of `foo` to `a`), this is simply a 
parse error and the user must include a backslash or a semicolon 
after `foo` to disambiguate.

We are more conservative about this than we should be and 
therefore disallow some code that isn’t actually ambiguous, but 
in practice it doesn’t seem to be much of a problem.

Having said all that, D is fine with semicolons and should keep 
them.