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Writing Lua libraries that target several Lua implementations can be
a frustrating exercise in working around lots of small differences in
APIs and semantics they share (or rename, or omit). This library
provides the means to simply access deterministic implementations of
those APIs that have the the same semantics across all supported host
Lua implementations. Each function is as thin and fast an
implementation as is possible within that host Lua environment,
evaluating to the Lua C implementation with no overhead where host
semantics allow.

I am happy to announce release 1.0 of std.normalize.

Most of these functions started life in lua-stdlib, or one of the
recent offshoots.

## Noteworthy changes in release 1.0 (2016-05-08) [stable]

### New features (since lua-stdlib-41.2)

 - Initial release, now separated out from lua-stdlib.

 - Passing a table of module names to the result of requiring
   this module injects top-level normalized APIs into the module
   environment, and additionally loads the named modules. For
   compatibility across supported Lua hosts, this must be assigned
   back to _ENV:

      local _ENV = require "std.normalize" {
        strict = "std.strict",

 - New `argerror` to add unhandled argument type reporting to Lua
   functions; equivalent to `luaL_argerror` in the Lua C API.

 - `len` will return the length of whatever an object's `__tostring`
   metamethod returns (except that a `__len` metamethod is used first
   if available), before counting initial non-nil valued integer keys.

 - `rawlen` ignores metamethods, and always counts up to the last
   sequential non-nil valued element in a sequence.

 - `load` will load a string of valid Lua code or call the given
   function or functor argument to fetch strings, even in Lua 5.1.

   Note that, for consistency across host implementations, the
   optional mode and env arguments are currently not supported.

 - `math.tointeger` and `math.type` are available everywhere (within the
   limitations of representing all number as 53-bit floats on Lua 5.2
   and earlier).

 - New `os.exit` wrapper accepts a boolean argument, even in Lua 5.1;
   but is slightly slower than the host Lua implementation in order to
   diagnose explicit nil or floating-point arguments (os.exit () is
   still equivalent to os.exit (true)).

 - `package.searchpath` is available everywhere.

 - `str` is a fast specialization of std.string.render with all helper
   functions and abstractions inlined.

 - When `_DEBUG` specifies argchecking, normalized APIs all diagnose
   unsuitable types passed by the caller.

### Bug fixes

 - `getfenv (0)` now returns the global environment correctly in Lua

 - `getmetamethod` now handles functor metatable fields correctly,
   rather than nil as in previous releases. It's also considerably
   faster now that it doesn't use pcall any more.

 - `pack` now sets n field to number of arguments packed, even in Lua

### Incompatible changes

 - The output format of `str` skips initial sequence keys (compared to
   the output from `std.tostring`) in this new compact format, including
   stringification of tables using their `__tostring` metamethods.

Install it with LuaRocks using:

    luarocks install std.normalize 1.0