# Basic syntax again

def showArr(msg, b) 
  puts "#{msg}: " unless msg == nil
  puts b.join(', ') if b 
end

a = [1, 2, 3, 4, 5] 

showArr('Original array', a)
print "\n"

#reverse indexing
puts "First is #{a[0]}; last is #{a[-1]}"

# slice
b = a[2, 3]              # 3 elements starting from 2 [3, 4, 5] 
showArr('Slice', b)

# range slice
b = a[1..3]              # From 1 to 3 [2, 3, 4]
showArr('Range slice', b)

# End range slice
b = a[-3..-1]            # From -3 to -1 (same as 2 to 4) [3, 4, 5]
showArr('End slice', b)

# Straight assign 
b = a
b[2] = "dog"             # Replace element 2 [1, 2, "dog", 4, 5]
showArr('Element assign', b)

# Zero fill 
b[6] = "mouse"           # Add element 6, and nil element 5 [1, 2, "dog", 4, 5, nil, "mouse"]
showArr('Zero fill', b)

# Replace ranges
b[2, 3] = [5, 4, 3]      # Replace 3 elements starting at 2 [1, 2, 5, 4, 3, nil, "mouse"]
showArr('Replaced range', b)    

# Which can resize the array
b[0, 2] = "cat"          # Replace 2 elements starting at 0 with a single "cat" ["cat", 5, 4, 3, nil, "mouse"]
showArr('Rep Range Resize', b)    

# It can be used to insert stuff too
b[2, 0] = [24, 48, "hut"]# Insert 3 elements at position 2 ["cat", 5, 24, 48, "hut", 4, 3, nil, "mouse"]
showArr('Insert elements', b)    

# Range replace
b[1..4] = [11, 12, 13, 14]# Replace elements 1..4 ["cat", 11, 12, 13, 14, 4, 3, nil, "mouse"]
showArr('Replace range', b)    

# Range replace (diff size)
b[1..4] = [1, 2]         # Replace elements 1..4 with just two ["cat", 1, 2, 4, 3, nil, "mouse"]
showArr('Resize range', b)    

# Range remove 
b[5..6] = []             # Replace elements 5 and 6 with nothing ["cat", 1, 2, 4, 3 ]
showArr('Remove range', b)    

# End replace
b[-2, 2] = [3, 4]        # Replace elements 3 and 4 (swap 'em) ["cat", 1, 2, 3, 4]
showArr('Replace at end', b)    

# Range from end
b[-5..-4] = [0, 1]       # Replace elements 0 and 1 [0, 1, 2, 3, 4]
showArr('Range from end', b)    

showArr("\nFinal array", b)
showArr("'a' is changed also (ref assign)", a)

# Perl-style iteration
while (c = a.shift)
  puts c
end

# Flatten arrays
muldim = [[1, 2, 3], 4, [[5, 6], 7], 8, 9]
showArr('Original',muldim)

flat = muldim.flatten
showArr('New flattened',flat)

# Alternatively, flatten in place
muldim.flatten!
showArr('Flattened in place',muldim)