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removing whitespace all over
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@@ -8,31 +8,31 @@ contributors:
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---
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Red was created out of the need to get work done, and the tool the author wanted to use, the language of REBOL, had a couple of drawbacks.
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Red was created out of the need to get work done, and the tool the author wanted to use, the language of REBOL, had a couple of drawbacks.
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It was not Open Sourced at that time and it is an interpreted language, what means that it is on average slow compared to a compiled language.
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Red, together with its C-level dialect Red/System, provides a language that covers the entire programming space you ever need to program something in.
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Red is a language heavily based on the language of REBOL. Where Red itself reproduces the flexibility of the REBOL language, the underlying language Red will be built upon,
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Red/System, covers the more basic needs of programming like C can, being closer to the metal.
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Red is a language heavily based on the language of REBOL. Where Red itself reproduces the flexibility of the REBOL language, the underlying language Red will be built upon,
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Red/System, covers the more basic needs of programming like C can, being closer to the metal.
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Red will be the world's first Full Stack Programming Language. This means that it will be an effective tool to do (almost) any programming task on every level
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from the metal to the meta without the aid of other stack tools.
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Furthermore Red will be able to cross-compile Red source code without using any GCC like toolchain
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Red will be the world's first Full Stack Programming Language. This means that it will be an effective tool to do (almost) any programming task on every level
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from the metal to the meta without the aid of other stack tools.
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Furthermore Red will be able to cross-compile Red source code without using any GCC like toolchain
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from any platform to any other platform. And it will do this all from a binary executable that is supposed to stay under 1 MB.
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Ready to learn your first Red?
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```
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All text before the header will be treated as comment, as long as you avoid using the
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word "red" starting with a capital "R" in this pre-header text. This is a temporary
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shortcoming of the used lexer but most of the time you start your script or program
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with the header itself.
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The header of a red script is the capitalized word "red" followed by a
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All text before the header will be treated as comment, as long as you avoid using the
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word "red" starting with a capital "R" in this pre-header text. This is a temporary
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shortcoming of the used lexer but most of the time you start your script or program
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with the header itself.
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The header of a red script is the capitalized word "red" followed by a
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whitespace character followed by a block of square brackets [].
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The block of brackets can be filled with useful information about this script or
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The block of brackets can be filled with useful information about this script or
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program: the author's name, the filename, the version, the license, a summary of
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what the program does or any other files it needs.
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The red/System header is just like the red header, only saying "red/System" and
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The red/System header is just like the red header, only saying "red/System" and
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not "red".
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Red []
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@@ -49,21 +49,21 @@ comment {
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; Your program's entry point is the first executable code that is found
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; no need to restrict this to a 'main' function.
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; Valid variable names start with a letter and can contain numbers,
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; variables containing only capital A thru F and numbers and ending with 'h' are
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; forbidden, because that is how hexadecimal numbers are expressed in Red and
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; Valid variable names start with a letter and can contain numbers,
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; variables containing only capital A thru F and numbers and ending with 'h' are
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; forbidden, because that is how hexadecimal numbers are expressed in Red and
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; Red/System.
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; assign a value to a variable using a colon ":"
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my-name: "Red"
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reason-for-using-the-colon: {Assigning values using the colon makes
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the equality sign "=" exclusively usable for comparisons purposes,
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exactly what "=" was intended for in the first place!
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reason-for-using-the-colon: {Assigning values using the colon makes
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the equality sign "=" exclusively usable for comparisons purposes,
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exactly what "=" was intended for in the first place!
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Remember this y = x + 1 and x = 1 => y = 2 stuff from school?
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}
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is-this-name-valid?: true
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; print output using print, or prin for printing without a newline or linefeed at the
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; print output using print, or prin for printing without a newline or linefeed at the
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; end of the printed text.
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prin " My name is " print my-name
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@@ -77,20 +77,20 @@ My name is Red
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;
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; Datatypes
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;
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; If you know Rebol, you probably have noticed it has lots of datatypes. Red
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; does not have yet all those types, but as Red want to be close to Rebol it
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; If you know Rebol, you probably have noticed it has lots of datatypes. Red
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; does not have yet all those types, but as Red want to be close to Rebol it
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; will have a lot of datatypes.
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; You can recognize types by the exclamation sign at the end. But beware
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; names ending with an exclamation sign are allowed.
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; Some of the available types are integer! string! block!
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; You can recognize types by the exclamation sign at the end. But beware
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; names ending with an exclamation sign are allowed.
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; Some of the available types are integer! string! block!
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; Declaring variables before using them?
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; Red knows by itself what variable is best to use for the data you want to use it
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; for.
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; A variable declaration is not always necessary.
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; Declaring variables before using them?
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; Red knows by itself what variable is best to use for the data you want to use it
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; for.
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; A variable declaration is not always necessary.
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; It is considered good coding practise to declare your variables,
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; but it is not forced upon you by Red.
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; You can declare a variable and specify its type. a variable's type determines its
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; You can declare a variable and specify its type. a variable's type determines its
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; size in bytes.
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; Variables of integer! type are usually 4 bytes or 32 bits
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@@ -101,7 +101,7 @@ my-integer: 0
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type? my-integer
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integer!
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; A variable can be initialized using another variable that gets initialized
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; A variable can be initialized using another variable that gets initialized
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; at the same time.
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i2: 1 + i1: 1
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@@ -111,9 +111,9 @@ i2 - i1 ; result 1
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i2 * i1 ; result 2
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i1 / i2 ; result 0 (0.5, but truncated towards 0)
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; Comparison operators are probably familiar, and unlike in other languages you
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; Comparison operators are probably familiar, and unlike in other languages you
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; only need a single '=' sign for comparison.
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; There is a boolean like type in Red. It has values true and false, but also the
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; There is a boolean like type in Red. It has values true and false, but also the
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; values on/off or yes/no can be used
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3 = 2 ; result false
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@@ -125,15 +125,15 @@ i1 / i2 ; result 0 (0.5, but truncated towards 0)
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;
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; Control Structures
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;
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;
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; if
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; Evaluate a block of code if a given condition is true. IF does not return any value,
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; Evaluate a block of code if a given condition is true. IF does not return any value,
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; so cannot be used in an expression.
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if a < 0 [print "a is negative"]
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; either
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; Evaluate a block of code if a given condition is true, else evaluate an alternative
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; block of code. If the last expressions in both blocks have the same type, EITHER can
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; Evaluate a block of code if a given condition is true, else evaluate an alternative
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; block of code. If the last expressions in both blocks have the same type, EITHER can
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; be used inside an expression.
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either a < 0 [
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either a = 0 [
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@@ -147,7 +147,7 @@ either a < 0 [
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print ["a is " msg lf]
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; There is an alternative way to write this
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; There is an alternative way to write this
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; (Which is allowed because all code paths return a value of the same type):
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msg: either a < 0 [
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@@ -162,7 +162,7 @@ msg: either a < 0 [
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print ["a is " msg lf]
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; until
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; Loop over a block of code until the condition at end of block, is met.
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; Loop over a block of code until the condition at end of block, is met.
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; UNTIL does not return any value, so it cannot be used in an expression.
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c: 5
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until [
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@@ -172,11 +172,11 @@ until [
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]
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; will output:
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ooooo
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; Note that the loop will always be evaluated at least once, even if the condition is
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; Note that the loop will always be evaluated at least once, even if the condition is
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; not met from the beginning.
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; while
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; While a given condition is met, evaluate a block of code.
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; While a given condition is met, evaluate a block of code.
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; WHILE does not return any value, so it cannot be used in an expression.
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c: 5
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while [c > 0][
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@@ -206,7 +206,7 @@ print twice b ; will output 6.
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## Further Reading
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The main source for information about Red is the [Red language homepage](http://www.red-lang.org).
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The main source for information about Red is the [Red language homepage](http://www.red-lang.org).
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The source can be found on [github](https://github.com/red/red).
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@@ -218,4 +218,4 @@ Browse or ask questions on [Stack Overflow](stackoverflow.com/questions/tagged/r
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Maybe you want to try Red right away? That is possible on the [try Rebol and Red site](http://tryrebol.esperconsultancy.nl).
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You can also learn Red by learning some [Rebol](http://www.rebol.com/docs.html).
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You can also learn Red by learning some [Rebol](http://www.rebol.com/docs.html).
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