diff options
Diffstat (limited to 'lib/sqlalchemy/sql')
| -rw-r--r-- | lib/sqlalchemy/sql/functions.py | 4 | ||||
| -rw-r--r-- | lib/sqlalchemy/sql/visitors.py | 34 |
2 files changed, 19 insertions, 19 deletions
diff --git a/lib/sqlalchemy/sql/functions.py b/lib/sqlalchemy/sql/functions.py index 22f127fcc..5a480f0c3 100644 --- a/lib/sqlalchemy/sql/functions.py +++ b/lib/sqlalchemy/sql/functions.py @@ -33,11 +33,11 @@ class GenericFunction(Function): class next_value(Function): """Represent the 'next value', given a :class:`.Sequence` as it's single argument. - + Compiles into the appropriate function on each backend, or will raise NotImplementedError if used on a backend that does not provide support for sequences. - + """ type = sqltypes.Integer() name = "next_value" diff --git a/lib/sqlalchemy/sql/visitors.py b/lib/sqlalchemy/sql/visitors.py index a79168e75..6f2c82992 100644 --- a/lib/sqlalchemy/sql/visitors.py +++ b/lib/sqlalchemy/sql/visitors.py @@ -8,15 +8,15 @@ SQLAlchemy schema and expression constructs rely on a Python-centric version of the classic "visitor" pattern as the primary way in which -they apply functionality. The most common use of this pattern -is statement compilation, where individual expression classes match -up to rendering methods that produce a string result. Beyond this, -the visitor system is also used to inspect expressions for various -information and patterns, as well as for usage in +they apply functionality. The most common use of this pattern +is statement compilation, where individual expression classes match +up to rendering methods that produce a string result. Beyond this, +the visitor system is also used to inspect expressions for various +information and patterns, as well as for usage in some kinds of expression transformation. Other kinds of transformation use a non-visitor traversal system. -For many examples of how the visit system is used, see the +For many examples of how the visit system is used, see the sqlalchemy.sql.util and the sqlalchemy.sql.compiler modules. For an introduction to clause adaption, see http://techspot.zzzeek.org/2008/01/23/expression-transformations/ @@ -28,18 +28,18 @@ import re from .. import util import operator -__all__ = ['VisitableType', 'Visitable', 'ClauseVisitor', - 'CloningVisitor', 'ReplacingCloningVisitor', 'iterate', +__all__ = ['VisitableType', 'Visitable', 'ClauseVisitor', + 'CloningVisitor', 'ReplacingCloningVisitor', 'iterate', 'iterate_depthfirst', 'traverse_using', 'traverse', 'cloned_traverse', 'replacement_traverse'] class VisitableType(type): """Metaclass which assigns a `_compiler_dispatch` method to classes having a `__visit_name__` attribute. - + The _compiler_dispatch attribute becomes an instance method which looks approximately like the following:: - + def _compiler_dispatch (self, visitor, **kw): '''Look for an attribute named "visit_" + self.__visit_name__ on the visitor, and call it with the same kw params.''' @@ -92,7 +92,7 @@ class Visitable(object): __metaclass__ = VisitableType class ClauseVisitor(object): - """Base class for visitor objects which can traverse using + """Base class for visitor objects which can traverse using the traverse() function. """ @@ -144,7 +144,7 @@ class ClauseVisitor(object): return self class CloningVisitor(ClauseVisitor): - """Base class for visitor objects which can traverse using + """Base class for visitor objects which can traverse using the cloned_traverse() function. """ @@ -160,7 +160,7 @@ class CloningVisitor(ClauseVisitor): return cloned_traverse(obj, self.__traverse_options__, self._visitor_dict) class ReplacingCloningVisitor(CloningVisitor): - """Base class for visitor objects which can traverse using + """Base class for visitor objects which can traverse using the replacement_traverse() function. """ @@ -168,8 +168,8 @@ class ReplacingCloningVisitor(CloningVisitor): def replace(self, elem): """receive pre-copied elements during a cloning traversal. - If the method returns a new element, the element is used - instead of creating a simple copy of the element. Traversal + If the method returns a new element, the element is used + instead of creating a simple copy of the element. Traversal will halt on the newly returned element if it is re-encountered. """ return None @@ -232,7 +232,7 @@ def traverse_depthfirst(obj, opts, visitors): return traverse_using(iterate_depthfirst(obj, opts), obj, visitors) def cloned_traverse(obj, opts, visitors): - """clone the given expression structure, allowing + """clone the given expression structure, allowing modifications by visitors.""" cloned = util.column_dict() @@ -256,7 +256,7 @@ def cloned_traverse(obj, opts, visitors): def replacement_traverse(obj, opts, replace): - """clone the given expression structure, allowing element + """clone the given expression structure, allowing element replacement by a given replacement function.""" cloned = util.column_dict() |