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diff --git a/nim.html.markdown b/nim.html.markdown new file mode 100644 index 00000000..25b99e57 --- /dev/null +++ b/nim.html.markdown @@ -0,0 +1,259 @@ +--- +language: nim +filename: learnNim.c +contributors: + - ["Jason J. Ayala P.", "http://JasonAyala.com"] +--- + +Nim is a statically typed, imperative programming language that tries to give +the programmer ultimate power without compromises on runtime efficiency. This +means it focuses on compile-time mechanisms in all their various forms. + +Nim is efficient, expressive, and elegant. + +```nimrod + +var x: int # Declare a variable and its type +x = 1 # Assign it a value +var z = "Yep" # Declare and assign, with or without type annotations + +var # Several, with or without type annotations + letter: char = 'n' # One byte character + name = "Nimrod" # string + truth: bool = false # Common boolean operators: `and` `not` `or` + seconds: int = 42 + thoughts = """ +A great programming language +that everyone can enjoy! +""" # Multiline raw strings + boat: float + +let # Use let to declare and bind an variable *once*. + legs = 400 # legs is immutable. + arms = 2_000 # _ are ignored and are useful for long numbers. + +const # Constants are computed at compile time. This provides + debug = true # performance and is useful in compile time expressions. + aboutPi = 3.15 + compileBadCode = false + +when compileBadCode: # `when` is a compile time `if` + legs = legs + 1 # This error will never be compiled. + const input = readline(stdin) # const values must be known at compile time. + +discard 1 > 2 # The compiler will complain if the result of an expression + # is unused. `discard` bypasses this. + +discard """ +This can work as a +multiline comment +""" + +# +# Common Operations on Basic Types +# + +var nim = "Nimrod is a progamming language" +name = nim[0..5] + +# TODO More common operations? + +# +# Data Structures +# + +# Tuples + +var + child: tuple[name: string, age: int] # Tuples have *both* field names + today: tuple[sun: string, temp: float] # *and* order. + +child = (name: "Rudiger", age: 2) # Assign all at once with literal () +today.sun = "Overcast" # or individual fields. +today.temp = 70.1 + +# Sequences + +var + drinks: seq[string] + +drinks = @["Water", "Juice", "Chocolate"] # @[V1,..,Vn] is the sequence literal + +# +# Defining Your Own Types +# + +# Defining your own types puts the compiler to work for you. It's what makes +# static typing powerful and useful. + +type + Name = string # A type alias gives you a new type that is interchangable + Age = int # with the old type but is more descriptive. + Person = tuple[name: Name, age: Age] # Define data structures too. + +var + john: Person = ("John B.", 17) + newage: int = 18 # It would be better to use Age than int + +john.age = newage # But still works because int and Age are synonyms + +type + Cash = distinct int # `distinct` makes a new type incompatible with it's + Desc = distinct string # base type. + +var + money: Cash = 100.Cash # `.Cash` converts the int to our type + desc: Desc = "Interesting".Desc + +when compileBadCode: + john.age = money # Error! age is of type int and money is Cash + john.name = desc # Compiler says: "No way!" + +# +# More Types and Data Structures +# + +# Enumerations allow a type to be one of a limited number of values + +type + Directions = enum north, west, east, south + Colors = enum red, blue, green +var + orient = north # `orient` is of type Directions, with the value `north` + pixel = green # `pixel` is of type Colors, with the value `green` + +discard north > east # Enums are usually an "ordinal" type + +# Subranges specify a limited valid range + +type + DieFaces = range[1..20] # Only an int from 1 to 20 is a valid value +var + my_roll: DieFaces = 13 + +when compileBadCode: + my_roll = 23 # Error! + +# Arrays + +type + RollCounter = array[DieFaces, int] # Array's are fixed length and + DirNames = array[Directions, string] # indexed by any ordinal type. + Truths = array[42..44, bool] +var + rollCounter: RollCounter + directions: DirNames + truths: Truths + +truths = [false, false, false] # Literal arrays are created with [V1,..,Vn] +truths[42] = true + +directions[north] = "Ahh. The Great White North!" +directions[west] = "No, don't go there." + +my_roll = 13 +rollCounter[my_roll] += 1 +rollCounter[my_roll] += 1 + +var anotherArray = ["Default index", "starts at", "0"] + +# TODO common operations + +# +# IO and Control Flow +# + +# `case`, `readLine()` + +echo "Read any good books lately?" +case readLine(stdin) +of "no", "No": + echo "Go to your local library." +of "yes", "Yes": + echo "Carry on, then." +else: + echo "That's great; I assume." + +# `while`, `if`, `continue`, `break` + +import strutils as str +echo "I'm thinking of a number between 41 and 43. Guess which!" +var + answer: int = 42 + raw_guess: string + guess: int +while guess != answer: + raw_guess = readLine(stdin) + if raw_guess == "": + continue # `continue` restarts loop/block + guess = str.parseInt(raw_guess) + if guess == 1001: + echo("AAAAAAGGG!") + break + elif guess > answer: + echo("Too high.") + elif guess < answer: + echo("Too low") + else: + echo("Yeeeeeehaw!") + +# +# Iteration +# + +# Iterate with the `for` keyword +# TODO `for` examples for strings, arrays, etc + +for elem in ["Yes", "No", "Maybe so"]: + echo elem + +# string iterators + +let myString = """ +an example +string to +play with +""" + +for line in splitLines(myString): + echo(line) + +# +# Procedures +# + +type Answer = enum yes, no + +proc ask(question: string): Answer = + echo(question, " (y/n)") + while true: + case readLine(stdin) + of "y", "Y", "yes", "Yes": + return Answer.yes # Enums can be qualified + of "n", "N", "no", "No": + return Answer.no + else: echo("Please be clear: yes or no") + +proc addSugar(amount: int = 2) = # Default amount is 2, returns nothing + for a in 1..amount: + echo a, " sugar..." + +case ask("Would you like sugar in your tea?") +of yes: + addSugar(3) +of no: + echo "Oh do take a little!" + addSugar() +# No need for an `else` here. only `yes` and `no` are possible. + +``` + +## Further Reading + +* [Home Page](http://nimrod-lang.org) +* [Download](http://nimrod-lang.org/download.html) +* [Community](http://nimrod-lang.org/community.html) +* [FAQ](http://nimrod-lang.org/question.html) +* [Documentation](http://nimrod-lang.org/documentation.html) +* [Manual](http://nimrod-lang.org/manual.html) +* [Standard Libray](http://nimrod-lang.org/lib.html) |