Groovy Conditionals

if (true) assert true

if (1)
assert true
else
assert false

def result = 5 > 3 ? 'x' : 'y'
assert result == 'x'

// name supplied as a parameter, or not

// result = name ? name : 'Elvis'
// like nvl(varname,literal) in SQL

def greet(name) { "${name ?: 'Elvis'} has left the building" }
assert greet() == 'Elvis has left the building'
assert greet(null) == 'Elvis has left the building'
assert greet('Priscilla') == 'Priscilla has left the building'

def hello(name = 'World') { "Hello, $name!" }
assert hello() == 'Hello, World!'
assert hello(null) == 'Hello, null!'
assert hello('Dolly') == 'Hello, Dolly!'

// 'reused' from Groovy In Action -- buy it!
switch (10) {
case 0:    assert false; break
case 0..9:    assert false; break
case [8,9,11]:   assert false; break
case Float:   assert false; break
case { it%3 == 0 }: assert false; break
case ~/../:   assert true; break
default:    assert false
}

def val
def a, b, c
// long form (Java like)
if (a != null) {
if (a.b != null) {
  val = a.b.c
} else {
  val = null
}
} else {
val = null
}

// easier way (Groovy)
val = a?.b?.c

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