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docs/en/tapdance.md

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+# Tap Dance
+
+Tap dance is a way to allow a single physical key to work as multiple logical
+keys / actions without using layers. With basic tap dance, you can trigger these
+"nested" keys or macros through a series of taps of the physical key within a
+given timeout.
+
+The resulting "logical" action works just like any other key - it can be pressed
+and immediately released, or it can be held. For example, let's take a key
+`KC.TD(KC.A, KC.B)`. If the tap dance key is tapped and released once quickly,
+the letter "a" will be sent. If it is tapped and released twice quickly, the
+letter "b" will be sent. If it is tapped once and held, the letter "a" will be
+held down until the tap dance key is released. If it is tapped and released once
+quickly, then tapped and held (both actions within the timeout window), the
+letter "b" will be held down until the tap dance key is released.
+
+To use this, you may want to define a `tap_time` value in your keyboard
+configuration. This is an integer in milliseconds, and defaults to `300`.
+The timeout is reset after each tap and every tapdance sequence can also define
+an individual `tap_time`.
+
+You'll then want to create a sequence of keys using `KC.TD(KC.SOMETHING,
+KC.SOMETHING_ELSE, MAYBE_THIS_IS_A_MACRO, WHATEVER_YO)`, and place it in your
+keymap somewhere. The only limits on how many keys can go in the sequence are,
+theoretically, the amount of RAM your MCU/board has.
+
+Tap dance supports all `HoldTap` based keys, like mod tap, layer tap, oneshot...
+it will even honor every option set for those keys.
+Individual timeouts and prefer hold behavior for every tap in the sequence?
+Not a problem.
+
+Here's an example of all this in action:
+
+```python
+from kmk.keycodes import KC
+from kmk.handlers.sequences import send_string
+from kmk.modules.tapdance import TapDance
+
+keyboard = KMKKeyboard()
+
+tapdance = TapDance()
+tapdance.tap_time = 750
+keyboard.modules.append(tapdance)
+
+EXAMPLE_TD = KC.TD(
+    # Tap once for "a"
+    KC.A,
+    # Tap twice for "b", or tap and hold for "left control"
+    KC.MT(KC.B, KC.LCTL, prefer_hold=False),
+    # Tap three times to send a raw string via macro
+    send_string('macros in a tap dance? I think yes'),
+    # Tap four times to toggle layer index 1, tap 3 times and hold for 3s to
+    # momentary toggle layer index 1.
+    KC.TT(1, tap_time=3000),
+)
+
+# make the default tap time really short for this tap dance:
+EXAMPLE_TD2 = KC.TD(KC.A, KC.B, tap_time=80)
+
+
+keyboard.keymap = [[ ...., EXAMPLE_TD, ....], ....]
+```