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libraries/FastLED/src/fl/_readme

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+This directory holds core functionality of FastLED.
+
+Every class/struct/function in this directory must be under the
+namespace fl, except for special cases.
+
+This is done because according to the the Arduino build system,
+all headers/cpp/hpp files in the root the src directory will be in global
+scope and other libraries can #include them by mistake.
+
+This has happened so many times that I've just gone ahead and migrated all
+the new code to this directory, to prevent name collisions.
+
+# When to put stuff in `fl` and not `fx`
+
+If it's a visualizer, put it in the `fx` fodler. If it it's something to help to build a visualizer then you put it here.