Package lepl :: Package stream :: Module core

Module core

Default implementations of the stream classes.

A stream is a tuple (state, helper), where state will vary from location to location, while helper is an "unchanging" instance of StreamHelper, defined below.

For simple streams state can be a simple integer and this approach avoids the repeated creation of objects. More complex streams may choose to not use the state at all, simply creating a new helper at each point.

Classes

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StreamHelper
The interface that all helpers should implement.

MutableMaxDepth
Track maximum depth (offset) reached and the associated stream.

HashKey
Used to store a value with a given hash.

Variables

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_StreamHelper = ABCMeta('_StreamHelper', (object,), {})
ABC used to identify streams.

DUMMY_HELPER = object()
Allows tests to specify an arbitrary helper in results.

s_key

s_kargs

s_fmt

s_debug = lambda stream:
Invoke helper.debug()

s_next

s_join = lambda stream,* values:
Invoke helper.join(*values)

s_empty = lambda stream:
Invoke helper.empty(state)

s_line = lambda stream, empty_ok:
Invoke helper.line(state, empty_ok)

s_len = lambda stream:
Invoke helper.len(state)

s_stream

s_deepest = lambda stream:
Invoke helper.deepest()

s_delta = lambda stream:
Invoke helper.delta(state)

s_eq = lambda stream1, stream2:
Compare two streams (which should have identical helpers)

s_id = lambda stream:
Access the ID attribute.

s_factory = lambda stream:
Access the factory attribute.

s_max = lambda stream:
Access the max attribute.

s_new_max = lambda stream:
Invoke helper.new_max(state).

s_global_kargs = lambda stream:
Access the global_kargs attribute.

s_cache_level = lambda stream:
Access the cache_level attribute.

s_cacheable = lambda stream:
Is the stream cacheable?