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# A GRIB file handle meant for use in a context manager.

# Individual messages can be accessed using the ``next`` method.
# (This is the Iterator Protocol: https://wiki.python.org/moin/Iterator)
# it is also possible to iterate over each message in the file::

# Usage::
>>> with GribFile(filename) as grib:
...     # Print number of messages in file
...     len(grib)
...     # Open all messages in file
...     for msg in grib:
...         print(msg[key_name])
...     len(grib.open_messages)
>>> # When the file is closed, any open messages are closed
>>> len(grib.open_messages)
0

# A GRIB message.

# Each ``GribMessage`` is stored as a key/value pair in a dictionary-like
# structure. It can be used in a context manager or by itself. When the
# ``GribFile`` it belongs to is closed, the ``GribFile`` closes any open
# ``GribMessage``s that belong to it. If a ``GribMessage`` is closed before
# its ``GribFile`` is closed, it informs the ``GribFile`` of its closure.

# Scalar and vector values are set appropriately through the same method.

# ``GribMessage``s can be instantiated from a ``GribFile``, cloned from
# other ``GribMessage``s or taken from samples. Iterating over the members
# of a ``GribFile`` extracts the ``GribMessage``s it contains until the
# ``GribFile`` is exhausted.

# Usage::
>>> with GribFile(filename) as grib:
...     # Access a key from each message
...     for msg in grib:
...         print(msg[key_name])
...     # Report number of keys in message
...     len(msg)
...     # Report message size in bytes
...     msg.size
...     # Report keys in message
...     msg.keys()
...     # Set scalar value
...     msg[scalar_key] = 5
...     # Check key's value
...     msg[scalar_key]
...     msg[key_name]
...     # Array values are set transparently
...     msg[array_key] = [1, 2, 3]
...     # Messages can be written to file
...     with open(testfile, "w") as test:
...         msg.write(test)
...     # Messages can be cloned from other messages
...     msg2 = GribMessage(clone=msg)
...     # If desired, messages can be closed manually or used in 'with'
...     msg.close()

# A BUFR file handle meant for use in a context manager.

# Individual messages can be accessed using the ``next`` method. Of course,
# (This is the Iterator Protocol: https://wiki.python.org/moin/Iterator)
# itIt is also possible to iterate over each message in the file::

# Usage::
>>> with BufrFile(filename) as bufr:
...     # Print number of messages in file
...     len(bufr)
...     # Open all messages in file
...     for msg in bufr:
...         print(msg[key_name])
...     len(bufr.open_messages)
>>> # When the file is closed, any open messages are closed
>>> len(bufr.open_messages)
0

# A BUFR message.

# Each ``BufrMessage`` is stored as a key/value pair in a dictionary-like
# structure. It can be used in a context manager or by itself. When the
# ``BufrFile`` it belongs to is closed, the ``BufrFile`` closes any open
# ``BufrMessage``s that belong to it. If a ``BufrMessage`` is closed before
# its ``BufrFile`` is closed, it informs the ``BufrFile`` of its closure.

# Scalar and vector values are set appropriately through the same method.

# ``BufrMessage``s can be instantiated from a ``BufrFile``, cloned from
# other ``BufrMessage``s or taken from samples. Iterating over the members
# of a ``BufrFile`` extracts the ``BufrMessage``s it contains until the
# ``BufrFile`` is exhausted.

# Usage::

>>> with BufrFile(filename) as bufr:
...     # Access a key from each message
...     for msg in bufr:
...         print(msg[key_name])
...     # Report number of keys in message
...     len(msg)
...     # Report message size in bytes
...     msg.size
...     # Report keys in message
...     msg.keys()
...     # Set scalar value
...     msg[scalar_key] = 5
...     # Check key's value
...     msg[scalar_key]
...     msg[key_name]
...     # Array values are set transparently
...     msg[array_key] = [1, 2, 3]
...     # Messages can be written to file
...     with open(testfile, "w") as test:
...         msg.write(test)
...     # Messages can be cloned from other messages
...     msg2 = BufrMessage(clone=msg)
...     # If desired, messages can be closed manually or used in 'with'
...     msg.close()