for ... else

[odino]

No description provided.

[mingwho]

Will for... else work with both For and For In expression?
Something like these

for i in 0..-1 {
    echo("inside for")
} else {
    echo("inside else")
}

for i = 0; i < 10; i++ {
    if i == 11 { echo ("inside for") } 
} else {
        echo("inside else")
}

[odino]

I think for in is enough. The basic idea is to run some code if list in the for in is empty

users = db.query("SELECT students WHERE age > 20")

for user in users {
  print(user)
} else {
  print("We don't have students above the age of 20")
}

which you would have to write like this without for else:

users = db.query("SELECT students WHERE age > 20")

if users.len() {
  for user in users {
    print(user)
  }
} else {
  print("We don't have students above the age of 20")
}

or

users = db.query("SELECT students WHERE age > 20")

if users.len() {
  for user in users {
    print(user)
  }

  return
}
 
print("We don't have students above the age of 20")

BTW python does this differently (the else runs when there's no break), but I believe it'd be more useful to keep for ... else for other use cases. Jinja does this (even though it's a templating language):

<ul>
{% for user in users %}
    <li>{{ user.username|e }}</li>
{% else %}
    <li><em>no users found</em></li>
{% endfor %}
</ul>