How can i take a string of words and replace / switch the first and last words with each other?

I.E.
original - this is a sentence
new - sentence is a the

use the split() function to split the sentence on white space, switch the first and last elements in the array, then loop over the array and concatenate each word to a new string

if the string is longer than 3 words then everything with be in reverse, not just the first and last word

I'd do something like this with a little bit of regex:


1. ( ) brackets represent capturing groups. first group captures the first word, second group captures all the words excluding the first and last word. third group is the last word.
2. in the replace method you swap the first and third group around to get the result you want. $1$2$3 ==> $3$2$1

This post was edited by iasip11 on Mar 5 2017 12:43pm

That regex won't work in a lot of different scenarios.

Try:
^(\W*)(\w+)(.+?)(\w+)(\W*)$

edit: Replace would be $1$4$3$2$5

This post was edited by waraholic on Mar 5 2017 04:11pm

edit: nvm, had a brainfar here ==> the third capturing group's ? quantifier isnt necessary because (.+) <== counts whitespace too so you'd always expect one between two words.
and youre right in bringing up the cases with non word chars, but OP doesn't suggest we include them

how do we use your regex though, with the replace?


edit: ok, gotcha. gj covering all possible cases.

This post was edited by iasip11 on Mar 5 2017 04:43pm

var sent = "programming in javascript sucks"

var arr = sent.split(" ");
var firstWord = arr.shift();
var lastWord = arr.pop();

arr.push(firstWord);
arr.unshift(lastWord)

sent = arr.join (" ");