% This file is simply the “tangled” code of oz-demo.org;
% it is the “raw” source code, provided for your convenience.

{Browse 'Hello world'}

declare
  S = 'Hello world'

{Browse S}

declare
`A fancier greeting` = 'A pleasure to make you acquaintance, my good fellow.'

{Browse `A fancier greeting`}

declare
`An alphanumeric atom` = this_Is_An_Atom
`A printable characters atom` = 'This is also an atom.'
`A quoted keyword` = 'if'

{Browse `An alphanumeric atom`}
{Browse `A printable characters atom`}
{Browse `A quoted keyword`}

{Browse 123}   % integer
{Browse 1.23}  % floating point
{Browse &{ }   % character ({ is 123 in ASCII)
{Browse 0123}  % octal (leading 0)
{Browse 0x123} % hexidecimal (leading 0x)

{Browse true}
{Browse false}

{Browse nil}
{Browse (1 | 2 | 3 | nil)}
{Browse [1 2 3]}

{Browse "Hello world"}
{Browse [&H &e &l &l &o &  &w &o &r &l &d]}
{Browse ""}

declare
  X = my_record_name(
        descr : 'A record carrying this string and an integer'
        a_num : 123)

{Browse X}
{Browse X.descr}
{Browse X.a_num}

declare
X = r('I am field 1. Field 2 is 123. Field 3 is true.' 123 true)

{Browse X.1}
{Browse X.2}
{Browse X.3}

declare
  L = [1 2 3]
  `Explicit L` = '|'(1 '|'(2 '|'(3 nil)))

{Browse L.1}
{Browse L.2}
{Browse `Explicit L`}

{Browse (if true then 'true is true.' end)}

{Browse (if true then 'First branch' else 'Second branch' end)}

if false then {Browse 'No else clause here.'} end

{Browse (if false then 'No.'
     elseif false then 'No.'
                  else 'Yes.'
        end)}

declare
  L = [1 2 3]

{Browse (case L of
              nil       then 'Empty'
           [] _|nil     then 'Singleton'
           [] _|_|nil   then 'Length 2'
           [] _|_|_|nil then 'Length 3'
                        else 'Longer than 3'
        end)
}

{Browse 1 == 1}
{Browse 1 =< 1}
{Browse 1 >= 1}
{Browse 1 <  1}
{Browse 1 >  1}

{Browse atom1     == atom2    }
{Browse "String1" == "String2"}
{Browse [1 2 3]   == [1 2 3 4]}
{Browse true      == false    }
{Browse r(1 2 3)  == r(2 3 4) }

{Browse abc < bcd}
{Browse abc < abcd}

% {Browse [1] < [2]}   % Cannot compare lists!

{Browse {And false false}}
{Browse {And false true }}
{Browse {And true  false}}
{Browse {And true  true }}

%1   % Cannot “execute” an expression!

declare
  fun {Exp M N}
    if N == 0 then 1 else M * {Exp M (N - 1)} end
  end

{Browse {Exp 2 5}}

declare
  fun {F}
    5
  end

declare
  fun {F}
    {Browse 10} % do something
    10          % return a value
  end

declare
fun {Exp M}
  fun {$ N}
    if N == 0 then 1 else M * {{Exp M} (N - 1)} end
  end
end

{Browse {{Exp 5} 5}}

declare
fun {Exp M N}
  if N == 0 then 1 else M * {Exp M (N - 1)} end
end

{Browse {Exp 5 5000}}

declare
  fun {Step2 M}
    if M > 1 then {Step1 M - 2} else M end
  end

  fun {Step1 M}
    if M > 0 then {Step2 M - 1} else M end
  end

  fun {MyPlan M}
    {Step1 M}
  end