greggirwin

opt: func [
	"If condition is TRUE, return value, otherwise return empty value of the same type"
	condition
	value "Some types, e.g., word types, return none if condition is false."
][
	either condition [ value ][ attempt [make value 0] ]
]

;opt true 'a
;opt true "A"

greggirwin

Red [
	File: 	 %greggs-mezz.red
	Author:  "Gregg Irwin"
	Purpose: "An interim mezzanine dump, while Red is still moving fast."
	Tabs:	 4
	Comment: {
		Not everything here has been well-tested or, well, tested. Most
		of the functions are ports from R2, with many more to come. I'm
		combining everything in one file for ease of experimentation, so
		you don't have to worry about includes or dependencies with the

greggirwin

Red [
	Title:   "math-lab.red"
	Author:  "Gregg Irwin"
	File: 	 %math-lab.red
	Needs:	 'View
	Purpose: {
		Experiment, to see what an interactive "Lab" tool might look 
		like, for general language functions. i.e., take the idea of
		font-lab, effect-lab, gradient-lab, etc., and apply it to
		functions to aid in language discovery and learning.

greggirwin

Red [
	Title:   "trig-lab.red"
	Author:  "Gregg Irwin"
	File: 	 %trig-lab.red
	Needs:	 'View
	Purpose: {
		See %math-lab comments for details. This script focuses 
		on trigonometric functions.
	}
]

greggirwin

Red [
	File:   %menu.red
	Author: "Gregg Irwin"
]

; The menu dialect in Red is easy. When making a face, you use `menu:`
; followed by a block of [string! block!] pairs, where the string is the
; text of the top level menu and the block is a simple dialect that 
; defines the drop-down menu items. Each item can be either a string!
; followed by a word!, or the special separator marker of '---. That's it.

greggirwin

; A number of languages have `take-while/drop-while` funcs. This is just to show how you
; can build them in Red.

; This model can be applied to any function that has a `/part` refinement, or extended in
; any number of ways. We don't yet have a standard `apply` or `refine` function in Red.
; Once we do, a more general HOF version could take the action as an arg, as well as the
; test to apply.

; Should this return the position, like FIND, rather than an integer?
; No match would then mean a NONE result. REMOVE/TAKE/COPY with /PART

greggirwin

; It might seem like just a party trick, out of context. The goal is not "look how 
; we can twist the language around!". Think, instead, of how you can use the language 
; to most clearly express intent in different domains, or for different users. Quite 
; often, when a user wants a different way to express things, we can accommodate them. 
; It's also true that we can suggest a form that exists natively in Red, and they will 
; be just as happy.
;
; Don't twist the language because you can. But don't be afraid to when it helps.

```

greggirwin

Red [
	title:   "Paint"
	Author:  [REBOL version "Frank Sievertsen" Red port "Gregg Irwin"]
	File: 	 %paint-with-time-travel.red
	Tabs:	 4
	Needs:	 View
	version: 0.0.3
	Notes:   {
		The original didn't have time travel.

greggirwin

Setup

First, thanks to everyone for taking time to read the proposal, do their own research, and offer suggestions. I don't know how to export messages from Gitter, so I'm afraid comments there may be lost to time. The REP is a wiki, so you can post your thoughts there. Wiki conversation isn't effective, but if we each have a comment section, we can put our interim and final thoughts there as we move forward. Or Peter can say if we would prefer to have people post things here for him to curate there.

greggirwin

Red [
	author: "Gregg Irwin"
]

comment {
	From Gitter, @this-gavagai asked about modeling in Red compared to modeling
	in traditional OOP languages. Here's the concrete example given:

	"
	Imagine you wanted to simulate economic dynamics in a third world village. You