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--- programming:elixir:hello_world [2023/04/25 07:09] – Small changes ateixeira
+++ programming:elixir:hello_world [2023/05/02 14:52] (current) – ateixeira
@@ Line 3: / Line 3: @@
 <code elixir>
 IO.puts("Hello world!")
+# Same as IO.puts but do not add a new line at the end
+IO.write("Hello world !")
 </code>
@@ Line 16: / Line 19: @@
 h
 </code>
+> Kernel is Elixir's default environment
+> In Elixir, (almost) everything is a function
 ----
-> On elixir, functions do not modify values. Functions transforms values on output.
+==== Reading values ====
+<code elixir>
+name = IO.gets("Salut, comment tu t'appelles ? ")
-Example :
+IO.write("Salut " <> name)
+</code>
+----
+==== Atom ====
+> An atom type represents a fixed constant. The atom value is simply its own name.
 <code elixir>
-iex(40)> d1 = ~D[2023-04-25]
+# All atoms are preceded with a :
-~D[2023-04-25]
+variable = :an_atom
 </code>
+==== Cond ===
+> Cond follows the first path that evaluates to true. If no path evaluates to true, an error is raised by the runtime.
 <code elixir>
-iex(41)> Date.add(d1,5)
+cond do
-~D[2023-04-30]
+    x > 10 -> :this_might_be_the_way
+    y < 7 -> :or_that_might_be_the_way
+    true -> :this_is_the_default_way
+end
 </code>
+==== _ (Underscore) ====
+> When there is a _ instead of a variable or a value, it means the value will be ignored and any value will be accepted
+<code elixir>
+{_, denominator} = Float.ratio(0.25)
+# => {1, 4}
+# the variable `denominator` is bounded to the value 4
+</code>
+<code elixir>
+[1, _, 3] = [1, "toto", 3]
+# => [1, "toto", 3]
+</code>
+==== Sigils ( symbols with magical powers ) ====
+>A sigil is an alternative syntax for representing and working with literals
+>A sigil starts with a tilde (~), followed by an upper- or lowercase letter, some delimited content, and perhaps some options
+> The delimiters can be <...>, {...}, [...], (...), |...|, /.../, "...", and '...'
+<code elixir>
+The letter determines the sigil’s type:
+~C  A character list with no escaping or interpolation
+~c  A character list, escaped and interpolated just like a single-quoted string
+~D  A Date in the format yyyy-mm-dd
+~N  A naive (raw) DateTime in the format yyyy-mm-dd hh:mm:ss[.ddd]
+~R  A regular expression with no escaping or interpolation
+~r  A regular expression, escaped and interpolated
+~S  A string with no escaping or interpolation
+~s  A string, escaped and interpolated just like a double-quoted string
+~T  A Time in the format hh:mm:ss[.dddd]
+~W  A list of whitespace-delimited words, with no escaping or interpolation
+~w  A list of whitespace-delimited words, with escaping and interpolation
+</code>
+----
+==== For ====
+<code elixir>
+number = IO.gets("Salut, entre un nombre : ") |> String.trim() |> String.to_integer()
+for i <- 1..number do
+  IO.puts("#{i}")
+end
+</code>
+----
+> In elixir, values are not modified. Values are transformed on output.
+**Example** :
+<code elixir>
+name = "Toto"
+if (name == "Toto") do
+  IO.puts("Inside condition before name being changed: " <> name)
+  name = "Robin"
+  IO.puts("Inside condition after name being changed: " <> name)
+end
+IO.puts("Outside condition after name being changed: " <> name)
+</code>
+**Output** :
+<code elixir>
+Inside condition before name being changed: Toto
+Inside condition after name being changed: Robin
+Outside condition after name being changed: Toto
+</code>
+**Example with date** :
+<code elixir>
+d1 = ~D[2023-04-25]
+IO.puts(d1)
+IO.puts(Date.add(d1, 5))
+IO.puts(d1)
+</code>
+**Output** :
 <code elixir>
-iex(42)> d1
+-04-25
-~D[2023-04-25]
+-04-30
+-04-25
 </code>