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0 pointsvardump10y ago0 comments

Last I checked Javascript implementations were slower than LuaJIT. Cost of implementing Lua tables, meta-tables, co-routines, etc. in Javascript will be rather high. Anywhere between 2-50x. If native Lua engine is removed, you can just forget about it then.

So what you're saying doesn't make any sense for anything remotely performance sensitive.

0 comments

striking10y ago

It's a joke. Like haha, but serious, because some people actually believe this.

bryanlarsen10y ago

lua compiled to asm.js is 64% of the speed of lua native

https://kripken.github.io/lua.vm.js/lua.vm.js.html

pygy_10y ago

... which is about 10 times slower than the LuaJIT compiler used by OpenResty.

Touche10y ago

So that might be good enough in the browser but on the server where an optimized Lua engine exists, why?

daurnimator10y ago

That's not compiling lua to asm.js; it's running the lua vm in asm.js.

A straight up transpilation is other projects like lua.js. But you loose really nice core lua features like coroutines...

kybernetikos10y ago

> Cost of implementing Lua tables, meta-tables

Tables and meta tables are nearly identical to objects and prototypes in javascript. Why would the cost of implementing them be high?

fanf210y ago

JavaScript objects are indexed by strings. Lua tables are indexed by arbitrary objects. In JS a[1] and a["1"] are the same element but they are different in Lua. In Lua a[{}] is a new element indexed by the identity of the new object literal, and will be a different element every time the expression is evaluated.

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