ampersands and slashes stripped out of slugs

[alxndr]

In slugs for taxonomies or post permalinks, slashes (/\) and ampersands (&) are stripped out. More useful URLs would be created by turning slashes into hyphens, and ampersands into the word "and".

e.g.:

"songs by Lennon/McCartney"
expected slug: "songs-by-lennon-mccartney"
actual slug: "songs-by-lennonmccartney"

"Us & Them"
expected slug: "us-and-them"
actual slug: "us-them"

replaces slashes with hyphens in post title slugs and taxonomy term slugs; replaces ampersands with "and" and "&c" with "etc" in post title slugs

This patch doesn't extend the ampersand fix to category/tag slugs (but the slash fix works). Perhaps ampersands are being stripped out before the title hits sanitize_title_with_dashes() ? I haven't dug around enough yet...

Agree with the slash replacement.

Don't agree with the & replacement due to internationalization problems: if you write a blog in french, you won't want '&' to be replaced with 'and'.

Oh right. ('and') perhaps?

Arg... that should have been

__('and')

Related: #10823

We already have __(' and ') string in .pot from wp_sprintf_l(), so we probably can use it here.

How can I force to use the slash in the url? I want to use a slash in my post url, but when I save my custom slug in the post editor it gets stripped out. There should be