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doc/manual/source/language/value/float.md

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+# Float
+
+`Float` is the primitive type constraint for floating-point values.
+
+## Examples
+
+```dcdl
+ratio = Float;
+threshold = Float default 0.5;
+```
+
+## Relationship to Int
+
+`Int` and `Float` are distinct primitive type constraints.
+A `Float` constraint requires a concrete `Float`, and an `Int` constraint requires a concrete `Int`.
+
+Arithmetic and comparison expressions can treat `Int` and `Float` as numeric values.
+Mixed arithmetic produces a `Float` result.