Move config/unit.h to unit.h and it's own namespace

src/config/axis.h

@@ -1,9 +1,11 @@
 #pragma once
 #include <stdint.h>
-#include "unit.h"
+#include "../unit.h"
 
 namespace config {
 
+using namespace unit;
+
 /// Axis configuration data
 struct AxisConfig {
     bool dirOn; ///< direction ON state (for inversion)

src/unit.h

@@ -1,28 +1,27 @@
 #pragma once
 #include <stdint.h>
 
-// In this header we introduce a minimal Unit class that can be used for conformability,
+/// Introduce a minimal Unit class that can be used for conformability, type checking and
-// type checking and conversion at compile time. Template parameters are abused to create
+/// conversion at compile time. Template parameters are abused to create unique types,
-// unique types, which then can go through (explicit) overload and conversion. Despite
+/// which then can go through (explicit) overload and conversion. Despite looking
-// looking daunting, usage is quite straightforward once the appropriate aliases and
+/// daunting, usage is quite straightforward once the appropriate aliases and inline
-// inline operators are defined:
+/// operators are defined:
-//
+///
-// U_mm distance = 10.0_mm;
+/// U_mm distance = 10.0_mm;
-// auto another = 20.5_mm;
+/// auto another = 20.5_mm;
-// auto sum = distance + another;
+/// auto sum = distance + another;
-//
+///
-// auto angle = 15.0_deg;
+/// auto angle = 15.0_deg;
-// auto test = distance + angle; // compile time error
+/// auto test = distance + angle; // compile time error
-//
+///
-// Template parameters are only used for type checking. The Unit contains a single value
+/// Template parameters are only used for type checking. The Unit contains a single value
-// Unit<T>::v and is thus well suited for parameter passing and inline initialization.
+/// Unit<T>::v and is thus well suited for parameter passing and inline initialization.
-//
+///
-// Conversion to physical steps is done in modules::motion through the sister class
+/// Conversion to physical steps is done in modules::motion through the sister class
-// AxisUnit, which also ensures quantities from different axes are not mixed together.
+/// AxisUnit, which also ensures quantities from different axes are not mixed together.
-// AxisUnit are the normal units that should be used at runtime, which is why physical
+/// AxisUnit are the normal units that should be used at runtime, which is why physical
-// units and operators are not exported into the global namespace by default.
+/// units and operators are not exported into the global namespace by default.
-
+namespace unit {
-namespace config {
 
 /// Base units for conformability testing
 enum UnitBase : uint8_t {
@@ -86,4 +85,12 @@ static constexpr U_deg_s2 operator"" _deg_s2(long double deg_s2) {
     return { deg_s2 };
 }
 
-} // namespace config
+} // namespace unit
+
+// Inject literal operators into the global namespace for convenience
+using unit::operator"" _mm;
+using unit::operator"" _mm_s;
+using unit::operator"" _mm_s2;
+using unit::operator"" _deg;
+using unit::operator"" _deg_s;
+using unit::operator"" _deg_s2;