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Alexander Gladysh wrote:
> I personally often use such calls in my micro-DSLs. Like this:
> foo "name"
> {
>   bar "bar";
>   baz "baz";
> }
> I find this style to be shorter and to better express
> "declarativeness" of the code. Also it is arguable simpler for
> non-programmers to comprehend in some cases. 
> "Non-weird" equivalent would have too many braces to my taste:
> local tmp = foo("name")
> tmp({bar("bar1"); baz("baz")})
> I believe Lua would be a bit less elegant without parenthesis-free
> calls. 

I use similar syntax to describe userdata structures, and automatically
generate C structs, the bindings to Lua and the
serialization/loading/saving. It makes my struct definition looks very
close to what it would look like in C. Without parenthesis-free calls it
would make it much less readable. Here is an example:

struct 'ModelBoneDef' {
    int32 'animid';
    int32 'flags';
    int16_index 'parent';
    int16 'geoid';
    int32 'unknown';
    AnimationBlock(Vec3D) 'translation';
    AnimationBlock(PackedQuaternionAsShorts) 'rotation';
    AnimationBlock(Vec3D) 'scaling';
    Vec3D 'pivot';
} {
    __postload = function(ctype, self, file)
        if self.parent==0 then
            self.parent = nil
        return self

This syntactic sugar is one of the main strength of Lua as a
domain-specific language platform.