US International Extended keyboard layout
The “US International Extended” layout is sofware
(for Windows) that
lets you type conveniently texts in
Spanish, French, German, Portuguese, and dozens of other languages,
using normal US keyboard. It also contains a collection of commonly
needed special characters such as − (minus sign),
° (degree sign), and “smart” quotes.
Currently, this page only describes a draft
design of the layout. The implementation is in progress.
The backslash key \ has two possible places on
the keyboard. They are both shown in this presentation, even though each
keyboard has it in one place only.
The presentation above shows the meanings of keys so that
- the basic meaning (often coinciding with the keycap engraving) is in
the lower left part, except for lower case letters, which have been
omitted for clarity
- the effect achieved by using
Shift is in the upper left part
- the effect achieved by using
AltGr (right Alt) is in the lower right part
- the effect achieved by using
AltGrShift
is in the upper right part.
The character repertoire covered contains all ISO Latin 1 and
all Windows Latin 1 characters, all ISO Latin 2 characters, and
selection of other important characters. Thus, all official languages
of European countries using the Latin alphabet are covered.
A few commonly needed mathematical characters are included, but for
typing mathematical expressions, the
Math Keyboard layout is recommended.
Some characters are not immediately recognizable from their
shapes alone. For example, there are several comma-like symbols
on the keyboard. To see the exact definitions (Unicode numbers and
names of characters), you currently need to download the keyboard
layout and inspect it using e.g. the
Microsoft Keyboard Layout Creator
(MSKLC)
program. That program was used to create this layout, and it can
also be used to modify it.
Principles
- To produce a letter with a diacritic mark, press first the key or
combination of keys for the mark, then the base letter. For example, to produce
à, press first `, then A.
To produce the uppercase À, press
first `, then
ShiftA (the same way you
type A).
- Different other characters are typed using
AltGrShift
or
Shift
before pressing a normal key. Typically, the character so produced resembles
the character in the keycap in shape, name, or meaning in a manner that is easy
to see and to remember. For example, the ® sign is produced by typing
AltGrR.
- The backslash key \ acts as an auxiliary key
that modifies the meaning of the next key. For example,
if you press first \, then L,
you get the letter l with stroke, ł.
Diacritic marks
The first column of the following table shows a diacritic mark
when attached to the letter “a“ or (if the mark is not used
with that letter) to some other suitable letter.
| Name of the mark | Key combination | Examples of use
|
á | acute accent | AltGr` | Bogotá, fiancé
|
ǎ | caron (háček ) | AltGrV | Čapek
|
ç | cedilla | AltGr, | garçon
|
â | circumflex | Shift6 | rôle
|
ä | dieresis (two dots, umlaut) | \ . | Härnösand
|
ė | dot above | AltGr. | Klaipėda
|
ő | double acute | AltGrShift. | Petőfi
|
à | grave accent | ` | Città, à la maison
|
ą | ogonek | AltGrShift, | Wałęsa
|
å | ring above | AltGrQ | Ångström
|
ã | tilde | Shift` | São
|
Subscripts and superscripts
Superscript digits, superscript plus, and superscript minus can be
typed using the grave accent key `
followed by a digit key, the - (for minus),
or the = (for plus).
Corresponding subscript characters can be typed the same way but starting with
AltGr`
instead of
`.
For compatibility with the US-International layout,
superscript two and three can also be typed with
AltGr2
and
AltGr3.
Note that
AltGr0 does not
produce superscript zero but the degree sign.
Backslash escapes
The following table shows the effects of keys when preceded by a
backslash \.
Differences from US International
This layout differs from the US International layout distributed
as part of Windows by being somewhat more natural and by supporting a larger
repertoire of characters, including letters used in Eastern European
languages.
For example, the euro sign € and the yen sign ¥
are assigned to the natural combinations
AltGrE
and
AltGrE
instead of the rather arbitrary
AltGr5
and
AltGr-.
There are also some incompatibilities, i.e. US International Extended is not
a pure extension of US International. The following list describes
some features of
US International that do not work as such in US International Extended:
- US International has duplicate entries for some accented letters.
For example, the letter é can be typed in the systematic way, using a dead key,
' E, but also with
AltGrE.
Methods of the latter type are not used in US International Extended, since
such key combinations are better used for natural input of characters like
€.
- US International uses the apostrophe key
'
as a dead key for the acute accent. This is handy for writing words with acute accent,
but it makes typing the apostrophe and the quotation mark more difficult and tends to
cause errors. Although US International Extended has combinations for
“smart” quotes, it has been designed so that Ascii apostrophe and Ascii
quotes can be typed as easily as on the basic US keyboard layout. Inevitably, the use
of the acute accent becomes a little more difficult: you use
AltGr` for it.
- In US International Extended,
the backslash key \ is used as a dead key, for extending
character repertoire. In the rare cases where you need the backslash character, use
` . Similarly, to produce the vertical bar |, you
need to type
Shift` .
- Some keys for characters that are rarely used in natural language texts
have been assigned to more commonly needed characters in US International Extended.
This means that AltGr is needed to produce the character
engraved in the keycap. The keys
[
and
]
produce “smart” quotes; when used with the
Shift key, they produce
«angle» quotes (used e.g. in French).
Similarly, Shift- does not produce
the underline _ (you need to type
AltGrShift- for it)
but the minus sign −.
- Some special characters are assigned differently. For example, in US International,
the multiplication sign × is produced by typing
AltGr=.
US International uses the more natural
AltGrX, reflecting the common
practice of using the letter x as a substitute for ×.
- In the 1 key, the assignments of ¡ and ¹ have been reversed for uniformity.
Use on other QWERTY keyboards
The layout can be used on physical keyboards that differ from
the physical US keyboards.
The point is that the works independently of the engravings on the keys.
The instructions give above refer to
keys by their engravings on US keyboards, so you need to compare
the keywords and remember or write down the differences.
The layout can even be used e.g. on an AZERTY keyboard, but it can
be too awkward to remember that the key with engraving A produces the letter q, etc.
On a British keyboard, for example, there are no serious difficulties.
Most engravings are the same. Yet, you need to remember that e.g. to produce
a letter with tilde, such as ñ, you do not use the key with the tilde ~ engraved on it but the one with the not sign ¬ on it.