Add spec file (Thanks @daurnimator!), more examples, new rockspec.

examples/env.lua

@@ -0,0 +1,9 @@
+local F = require("F")
+
+local assert = assert
+local _ENV = {x = "foo"}
+function gee()
+   assert("foo" == x)
+   assert("foo" == F'{x}')
+end
+gee()

examples/fahrenheit.lua

@@ -0,0 +1,6 @@
+local F = require("F")
+
+local f = 99
+local c = (f-32)/9*5
+
+print(F"{f} degrees Fahrenheit is {c:%.2f} degrees Celsius")

examples/upvalue.lua

@@ -0,0 +1,15 @@
+
+local F = require("F")
+
+local u = "Hello"
+
+local function f()
+   local w = "World"
+   return function()
+      local gobo = "GOBO"
+      print(u .. " " .. w)
+      print(F"{u} {w} of {gobo}")
+   end
+end
+
+f()()

rockspecs/f-strings-0.2-1.rockspec

@@ -0,0 +1,25 @@
+package = "f-strings"
+version = "0.2-1"
+source = {
+   url = "git://github.com/hishamhm/f-strings",
+   tag = "v0.2",
+}
+description = {
+   summary = [[String interpolation for Lua.]],
+   detailed = [[
+      String interpolation for Lua, inspired by f-strings,
+      a form of string interpolation in Python 3.6.
+      It allows you to interpolate variables in strings
+      (including local variables) using the syntax:
+      str = F"The value of x is {x} and the value of y is {y:%.2f}."
+   ]],
+   homepage = "http://github.com/hishamhm/f-strings",
+   license = "MIT"
+}
+dependencies = {}
+build = {
+   type = "builtin",
+   modules = {
+      F = "F.lua",
+   }
+}

spec/F_spec.lua

@@ -0,0 +1,81 @@
+describe("string interpolation", function()
+	local F = require "F"
+	local assert = assert
+	it("works with literals", function()
+		assert.same("foo", F'{"foo"}')
+	end)
+	it("works with locals", function()
+		do
+			local x = "foo"
+			assert.same("foo", F'{x}')
+		end
+	end)
+	it("works with referenced upvalues", function()
+		do
+			local x = "foo"
+			(function()
+				assert.same("foo", x) -- reference the upvalue
+				assert.same("foo", F'{x}')
+			end)()
+		end
+	end)
+	it("fails with unreferenced upvalues", function()
+		do
+			(function()
+				local x = "foo"
+				return function()
+					assert.not_same("foo", F'{x}')
+				end
+			end)()()
+		end
+	end);
+	(_VERSION == "Lua 5.1" and it or pending)("works with setfenv'd functions", function()
+		setfenv(1, {x = "foo"})
+		assert.same("foo", x)
+		assert.same("foo", F'{x}')
+	end);
+	(_VERSION == "Lua 5.1" and pending or it)("works with _ENV scopes", function()
+		do
+			local _ENV = {x = "foo"}
+			assert.same("foo", F'{x}')
+		end
+	end);
+	(_VERSION == "Lua 5.1" and pending or it)("fails with _ENV as an unreferenced upvalue", function()
+		do
+			local _ENV = {x = "foo"}
+			(function()
+				assert.not_same("foo", F'{x}')
+			end)()
+		end
+	end);
+	(_VERSION == "Lua 5.1" and pending or it)("works with _ENV as a referenced upvalue", function()
+		do
+			local _ENV = {x = "foo"}
+			(function()
+				assert.same("foo", x) -- reference the upvalue
+				assert.same("foo", F'{x}')
+			end)()
+		end
+	end);
+	(_VERSION == "Lua 5.1" and pending or it)("fails with unreferenced upvalue in custom _ENV", function()
+		do
+			(function()
+				local _ENV = {x = "foo"}
+				return function()
+					assert.not_same("foo", F'{x}')
+				end
+			end)()()
+		end
+	end);
+	(_VERSION == "Lua 5.1" and pending or it)("works with referenced upvalue in custom _ENV", function()
+		do
+			(function()
+				local _ENV = {x = "foo"}
+				return function()
+					assert.same("foo", x) -- reference the upvalue
+					assert.same("foo", F'{x}')
+				end
+			end)()()
+		end
+	end)
+end)