stevedonovan

#!/usr/bin/lua
-- Flatten ALL those tidy tables and add environment lookup
local tables = {math,io,os,string,bit32}
setmetatable(_G,{
	__index = function(t,key)
		for _,m in ipairs(tables) do
			local v = m[key]
			if v ~= nil then return v end
		end	
		return os.getenv(key)

stevedonovan

What is a Trait?

In Rust, types containing data - structs, enums and any other 'aggregate' types like tuples and arrays - are dumb. They may have methods but that is just a convenience; they are just functions. Types have no relationship with each other.

Traits are the abstract mechanism for adding functionality to types and establishing relationships between them.

stevedonovan

Why Rust Closures are (Somewhat) Hard

The Easy Case: Lua

Since hard is always relative to something else, I'd like to start with a dynamic language. Functions in Lua are essentially anonymous and can capture variables from their environment (pretty much like with JavaScript, which Lua resembles in several important ways):

stevedonovan

Cargo Manages Crates

Cargo is an important feature of the Rust ecosystem, using a central repository of versioned packages and ensuring reproducible builds. It has learned important lessons from more ad-hoc solutions like Go's 'go get' and is miles ahead from what is available for C++; it is like Maven, except TOML is easier to write and read than XML.

So suggesting that it is not ideal for some situations may come across as being perverse. I've seen people

stevedonovan

use std::rc::Rc;
use std::cell::{RefCell,Ref, RefMut};
use std::ops::Deref;
use std::fmt;

#[derive(Clone)]
struct Shared<T> {
    v: Rc<RefCell<T>>
}

stevedonovan

include_directories("../src/")

add_library(xstr SHARED lily_xstr.c)
set_target_properties(
    xstr
    PROPERTIES
        PREFIX ""
        COMPILE_FLAGS "-fPIC -g"
)

stevedonovan

local debug = require 'debug'
-- from.lua
-- supports some useful shortcuts when creating locals from tables or modules
--   require 'from'
--   local sin,cos,tan = slots(3) from(math)
--   local import,printf = slots(2) from 'pl.utils'
--   local pretty,utils,xml = slots(3) from 'pl.*'
--
-- Uses the debug library, so it's not very fast - only use for top-level initialization!

stevedonovan

!_TAG_FILE_FORMAT	2	/extended format; --format=1 will not append ;" to lines/
!_TAG_FILE_SORTED	1	/0=unsorted, 1=sorted, 2=foldcase/
!_TAG_PROGRAM_AUTHOR	steve.j.donovan@gmail.com
!_TAG_PROGRAM_NAME	ltags	//
!_TAG_PROGRAM_URL	http://github.com/stevedonovan/ltags	/official site/
!_TAG_PROGRAM_VERSION	0.1	//
Q	fs\win32.lua	/^function Q(arg)$/;"	m	struct:luarocks.fs.win32
Q	fs\lua.lua	/^function Q(arg)$/;"	m	struct:luarocks.fs.lua
_	fs\lua.lua	/^local _, ftp = pcall(require, "socket.ftp")$/;"	v	file:
absolute_name	fs\win32.lua	/^function absolute_name(pathname, relative_to)$/;"	m	struct:luarocks.fs.win32

stevedonovan

require 'tablex'

local M = tonumber(arg[1]) or 10000
local N = tonumber(arg[2]) or 1000

local t_msg, t_start

function start_t (msg)
    t_msg = msg
    t_start = os.clock()

stevedonovan

#!/usr/bin/env lua

--[[  -- installing LDoc
function install()
--    requires('pl','Penlight')
--    install_script 'ldoc'
end
--]]

-- --[[