Method arguments in Ruby

Defaults, keyword arguments and splats on ordinary methods.

def brew(drink, size: "medium", extra_shot: false)
  desc = "#{size} #{drink}"
  desc += " + shot" if extra_shot
  desc
end

puts brew("latte")
puts brew("mocha", size: "large", extra_shot: true)

# a splat parameter collects any number of positional arguments
def total(*prices, tax: 0.0)
  (prices.sum * (1 + tax)).round(2)
end

puts total(3.5, 4.25)
puts total(10, 20, tax: 0.08)

How it works

1. Keyword arguments with defaults document the call site.
2. Callers override only the keywords they care about.
3. *prices collects any number of positional arguments into an array.

Keywords and builtins used here

• brew
• def
• end
• if
• puts
• total

The run, in numbers

Lines

16

Characters to type

374

Tokens

112

Three-star pace

85 tpm

At the three-star pace of 85 tokens a minute, this run takes about 79 seconds.

Type this snippet

Step 1 of 3 in Methods & blocks, step 16 of 29 in Language basics.

← Previous Next →