Add support for various tapping macros

A macro key can now be easily set to act as a modifier on hold, and
press a shifted key when tapped. Or to switch layers when held, and
again press a shifted key when tapped.

Various other helper defines have been created which send macros when
the key is pressed, released and tapped, cleaning up the
action_get_macro function inside keymap definitions.

The layer switching macros require a GCC extension - 'compound
statements enclosed within parentheses'. The use of this extension is
already present within the macro subsystem of this project, so its use
in this commit should not cause any additional issues.

MACRO_NONE had to be cast to a (macro_t*) to suppress compiler
warnings within some tapping macros.

quantum/quantum_keycodes.h

@@ -249,6 +249,7 @@ enum quantum_keycodes {
 #define MACROTAP(kc) (kc | QK_MACRO | FUNC_TAP<<8)
 #define MACRODOWN(...) (record->event.pressed ? MACRO(__VA_ARGS__) : MACRO_NONE)
 
+
 // L-ayer, T-ap - 256 keycode max, 16 layer max
 #define LT(layer, kc) (kc | QK_LAYER_TAP | ((layer & 0xF) << 8))
 

tmk_core/common/action_macro.h

@@ -20,11 +20,33 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include "progmem.h"
 
 
-#define MACRO_NONE      0
+
+typedef uint8_t macro_t;
+
+#define MACRO_NONE      (macro_t*)0
 #define MACRO(...)      ({ static const macro_t __m[] PROGMEM = { __VA_ARGS__ }; &__m[0]; })
 #define MACRO_GET(p)    pgm_read_byte(p)
 
-typedef uint8_t macro_t;
+// Sends press when the macro key is pressed, release when release, or tap_macro when the key has been tapped
+#define MACRO_TAP_HOLD(record, press, release, tap_macro) ( ((record)->event.pressed) ? \
+     ( ((record)->tap.count <= 0 || (record)->tap.interrupted) ? (press) : MACRO_NONE ) : \
+     ( ((record)->tap.count > 0 && !((record)->tap.interrupted)) ? (tap_macro) : (release) ) )
+
+// Holds down the modifier mod when the macro key is held, or sends macro instead when tapped
+#define MACRO_TAP_HOLD_MOD(record, macro, mod) MACRO_TAP_HOLD(record, (MACRO(D(mod), END)), MACRO(U(mod), END), macro)
+
+// Holds down the modifier mod when the macro key is held, or pressed a shifted key when tapped (eg: shift+3 for #)
+#define MACRO_TAP_SHFT_KEY_HOLD_MOD(record, key, mod) MACRO_TAP_HOLD_MOD(record, (MACRO(I(10), D(LSFT), T(key), U(LSFT), END)), mod)
+
+
+// Momentary switch layer when held, sends macro if tapped
+#define MACRO_TAP_HOLD_LAYER(record, macro, layer) ( ((record)->event.pressed) ? \
+     ( ((record)->tap.count <= 0 || (record)->tap.interrupted) ? ({layer_on((layer)); MACRO_NONE; }) : MACRO_NONE ) : \
+     ( ((record)->tap.count > 0 && !((record)->tap.interrupted)) ? (macro) : ({layer_off((layer)); MACRO_NONE; }) ) )
+
+// Momentary switch layer when held, presses a shifted key when tapped (eg: shift+3 for #)
+#define MACRO_TAP_SHFT_KEY_HOLD_LAYER(record, key, layer) MACRO_TAP_HOLD_LAYER(record, MACRO(I(10), D(LSFT), T(key), U(LSFT), END), layer)
+     
 
 
 #ifndef NO_ACTION_MACRO