Generalized list pattern match

[raviqqe]

Discussed in #1408

^{Originally posted by raviqqe September 3, 2022}

Problem

• Taking initial or last elements is common operations on lists.

Examples

• pen/examples/life-game/lifeGame.pen

  Line 110 in 7853a8b

  if [c1, ...cs] = cs {

• pen/examples/snake/entity/snake.pen

  Line 47 in 7853a8b

  Positions = \(s Snake) [Position] {

Solution

• Generalize if-list expressions.

if [x, y, z, ...xs, v, w] = xs {
  ...
} else {
  ...
}

References

• Deconstruction of multiple elements in if-list expression #979