Scala offers list comprehensions, which are a simple way to create lists. These are often used to convert one list into another, while applying some change to each entry. List comprehensions can also filter a list.<\/p>\n
For example, we can determine the length of words in a sentence:<\/p>\n
\nval x = \"The quick brown fox jumps over the lazy dog\".split(\" \")\ny: Array[Int] = Array(3, 5, 5, 3, 5, 4, 3, 4, 3)\n<\/pre>\nThen, we can filter it to only long words:<\/p>\n
\nval z = for (i <- x if i.length > 4) yield i \nz: Array[String] = Array(quick, brown, jumps)\n<\/pre>\nLet’s say we had a second sentence, and we wanted to find the words that are in both.<\/p>\n
We can do this with a for comprehension:<\/p>\n
For instance:<\/p>\n
\nval words1 = \"This is an example sentence about a lazy dog\".split(\" \")\nval words2 = \"The quick brown fox jumps over the lazy dog\".split(\" \")\n\nfor (\n i <- words1;\n j <- words2 if i.equals(j)\n) yield i\n\nres22: Array[String] = Array(lazy, dog)\n<\/pre>\nIt's worth noting that you can also use a numeric range:
\nYou can also use a numeric range:<\/p>\n
\nfor (i <- 0 to 5) yield i\n\nres11: scala.collection.immutable.IndexedSeq[Int] = \n Vector(0, 1, 2, 3, 4, 5)\n<\/pre>\n","protected":false},"excerpt":{"rendered":"Scala offers list comprehensions, which are a simple way to create lists. These are often used to convert one list into another, while applying some change to each entry. List comprehensions can also filter a list. For example, we can determine the length of words in a sentence: val x = “The quick brown fox … <\/p>\n