For instance, the registered trademark symbol ® is just option+r. ∑ is option-w. Diacritics are two-stroke combinations, to get é, you'd type option-e, which puts the ´ on the screen, and then type the e to complete the character.

Some of them definitely make more sense than others. ∑ looks like a sideways 'W", the trademark symbol is just a circled r, and the diacritic marks fit the character you'd commonly associate them with. (Guess what letter you hit to get ¨ over a letter?)

Beats copy/pasting out of character map, anyways!

And, after they ran out of mnemonics, they sprinkled the rest of the characters on the keyboard (almost; I think they tried hard to keep things memorable, but some combinations are just plain of the "if you don't know it, you 'll never guess". The Apple logo is on the k key, for instance (IIRC). Mnemonic? MaKintosh?)

"Diacritics are two-stroke combinations, to get é, you'd type option-e, which puts the ´ on the screen, and then type the e to complete the character."

That's the old way. Recent OS X has 'hold down the e key, a menu pops up, click the desired variant or type the digit shown next to it'.

Sure, but even making your own keyboard layout beats copypasting out of character map for any characters that you use regularly (and if you switch from US-English to US-International as your base layout, you get a lot characters that aren't on US-English for free without making a new layout.)

On a more serious note, several languages have that, Ruby included.

I think we're approaching the level of unicode penetration that this shouldn't really be much of a problem.

Incidentally, I think this will be much more useful in Japan and possibly parts of China than in the parts of the world that speak an indo-european language (and therefore has an easier time learning English).

But, those areas that doesn't speak native English is of course just a small market. /s

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    	}