It's fun to dream what a literal syntax for Ruby's Set class might look like...

set_literals.rb

# generic literal of symbols
<:earth, :wind, :fire>
# => Set.new [:earth, :wind, :fire]

# %e literal of symbols without interpolation
%e<earth wind fire>
# => Set.new [:earth, :wind, :fire]

# %E literal of symbols with interpolation
element = :wind
%E<earth #{element} fire>
# => Set.new [:earth, :wind, :fire]

# generic literal of strings
<'earth', 'wind', 'fire'>
# => Set.new ['earth', 'wind', 'fire']

# %t literal of strings with interpolation
%t<earth wind fire>
# => Set.new ['earth', 'wind', 'fire']

# %T literal of strings with interpolation
element = 'wind'
%T<earth #{element} fire>
# => Set.new ['earth', 'wind', 'fire']

# generic literal of arrays
<[1, 2], [2, 3]>
# => Set.new([1, 2]).merge([2, 3])

# generic literal of hashes
<{a: 1, b: 2}, {b: 1, c: 2}>
# => Set.new({a: 1, b: 2}).merge({b: 1, c: 2})