One’s syntax is designed to be familiar to people coming from C-like languages while being a bit simpler and more streamlined.
Scripts are stored in plain text files with a .one file extension. One does not compile ahead of time: programs are run directly from source, from top to bottom like a typical scripting language. Internally, programs are compiled to bytecode for efficiency, but that’s an implementation detail.
Line comments start with // and end at the end of the line:
// This is a comment.
Block comments start with /* and end with */. They can span multiple lines:
/* This
is
a
multi-line
comment. */
Unlike C, block comments can nest in One:
/* This is /* a nested */ comment. */
This is handy because it lets you easily comment out an entire block of code, even if the code already contains block comments.
One way to get a quick feel for a language’s style is to see what words it reserves. Here’s what One has:
as break class construct continue else false for foreign if import
in is null return static super this true var while
Naming rules are similar to other programming languages. Identifiers start with a letter or underscore and may contain letters, digits, and underscores. Case is sensitive.
hi
camelCase
PascalCase
_under_score
abc123
ALL_CAPS
Identifiers that start with underscore (_) are special in One. They are used to indicate fields in classes.
Newlines (\n) are meaningful in One. They are used to separate statements:
// Two statements:
System.print("hi") // Newline.
System.print("bye")
Sometimes, though, a statement doesn’t fit on a single line and jamming a newline in the middle would trip it up. To handle that, One has a very simple rule: It ignores a newline following any token that can’t end a statement.
System.print( // Newline here is ignored.
"hi")
In practice, this means you can put each statement on its own line and wrap them across lines as needed without too much trouble.