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+Exess
+=====
+
+Exess is a simple library for reading and writing [XSD][] datatypes.
+
+Exess is useful for applications that need to read/write common datatypes
+from/to strings, in a standard and locale-independent format.  It supports
+reading any valid syntax, and writing in canonical form.  The implementation is
+not complete, but includes support for all of the common datatypes that are
+generally useful (the XML-specific and partial Gregorian calendar datatypes are
+omitted).
+
+Conversion to a string and back is lossless for all supported values.  For
+example, writing a `float` number to a string then reading it back will yield
+the exact same `float` as the original value.
+
+The API consists mainly of simple read and write functions for each datatype.
+A variant type is also included which allows generic code to work with values
+of any type.  For flexibility, allocation is handled by the caller, making it
+possible to work on the stack, or read and write values to fields in some
+structure.  Syntax errors are reported with a descriptive error code and
+character offset, allowing friendly error messages to be produced.
+
+Supported Datatypes
+-------------------
+
+Exess supports reading and writing:
+
+  * `boolean`, like "false", "true", "0", or "1".
+
+  * `decimal`, like "1.234" (stored as `double`).
+
+  * `float` and `double`, like "4.2E1" or "4.2e1".
+
+  * The unbounded integer types `integer`, `nonPositiveInteger`,
+    `negativeInteger`, `nonNegativeInteger`, and `nonPositiveInteger` (stored
+    as `int64_t` or `uint64_t`).
+
+  * The fixed size integer types `long`, `int`, `short`, `byte`,
+    `unsignedLong`, `unsignedInt`, `unsignedShort`, and `unsignedByte`.
+
+  * `duration`, like "P1Y6M".
+
+  * `time`, like "12:30:00.00".
+
+  * `date`, like "2001-12-31".
+
+  * `hex`, like "EC5355".
+
+  * `base64`,like "Zm9vYmFy".
+
+Dependencies
+------------
+
+None, except the C standard library.
+
+Building
+--------
+
+A [Meson][] build definition is included which can be used to do a proper
+system installation with a `pkg-config` file, generate IDE projects, run the
+tests, and so on.  For example, the library and tests can be built and run like
+so:
+
+    meson setup build
+    cd build
+    ninja test
+
+Documentation
+-------------
+
+ * [API reference (single page)](https://drobilla.gitlab.io/exess/c/singlehtml)
+ * [API reference (paginated)](https://drobilla.gitlab.io/exess/c/html)
+
+See the [Meson documentation][] for more details on using Meson.
+
+ -- David Robillard <d@drobilla.net>
+
+[XSD]: https://www.w3.org/TR/xmlschema-2/
+
+[Meson]: https://mesonbuild.com/
+
+[Meson documentation]: https://mesonbuild.com/Quick-guide.html