diff options
Diffstat (limited to 'docs')
-rw-r--r-- | docs/YamlIO.rst | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/docs/YamlIO.rst b/docs/YamlIO.rst index dfb348da2f..76dd021f82 100644 --- a/docs/YamlIO.rst +++ b/docs/YamlIO.rst @@ -399,6 +399,42 @@ the above schema, a same valid YAML document is: name: Tom flags: [ pointy, flat ] +Sometimes a "flags" field might contains an enumeration part +defined by a bit-mask. + +.. code-block:: c++ + + enum { + flagsFeatureA = 1, + flagsFeatureB = 2, + flagsFeatureC = 4, + + flagsCPUMask = 24, + + flagsCPU1 = 8, + flagsCPU2 = 16 + }; + +To support reading and writing such fields, you need to use the maskedBitSet() +method and provide the bit values, their names and the enumeration mask. + +.. code-block:: c++ + + template <> + struct ScalarBitSetTraits<MyFlags> { + static void bitset(IO &io, MyFlags &value) { + io.bitSetCase(value, "featureA", flagsFeatureA); + io.bitSetCase(value, "featureB", flagsFeatureB); + io.bitSetCase(value, "featureC", flagsFeatureC); + io.maskedBitSetCase(value, "CPU1", flagsCPU1, flagsCPUMask); + io.maskedBitSetCase(value, "CPU2", flagsCPU2, flagsCPUMask); + } + }; + +YAML I/O (when writing) will apply the enumeration mask to the flags field, +and compare the result and values from the bitset. As in case of a regular +bitset, each that matches will cause the corresponding string to be added +to the flow sequence. Custom Scalar ------------- |