44 lines
1.1 KiB
Python
44 lines
1.1 KiB
Python
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from __future__ import unicode_literals
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class Renderer(object):
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def render(self, ast):
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"""Walks the AST and calls member methods for each Node type.
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@param ast {Node} The root of the abstract syntax tree.
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"""
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walker = ast.walker()
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self.buf = ''
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self.last_out = '\n'
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event = walker.nxt()
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while event is not None:
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type_ = event['node'].t
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if hasattr(self, type_):
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getattr(self, type_)(event['node'], event['entering'])
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event = walker.nxt()
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return self.buf
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def lit(self, s):
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"""Concatenate a literal string to the buffer.
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@param str {String} The string to concatenate.
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"""
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self.buf += s
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self.last_out = s
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def cr(self):
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if self.last_out != '\n':
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self.lit('\n')
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def out(self, s):
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"""Concatenate a string to the buffer possibly escaping the content.
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Concrete renderer implementations should override this method.
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@param str {String} The string to concatenate.
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"""
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self.lit(s)
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