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# Copyright 2004-2005 Gentoo Foundation |
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# Distributed under the terms of the GNU General Public License v2 |
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# |
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|
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"""A template handler/parser module. |
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|
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General Info: |
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|
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Variables can be set in one of two ways; either the param() or params() |
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method. The param() method takes two arguments, 'key', and 'value', where |
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'key is the name of the template parameter, and value is the value it |
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should be replaced with. |
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|
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This module uses caching to speed up template creation. Use the 'use_cache' |
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attribute to toggle caching. Also, remember to clean out the template cache |
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folder every once in a while as you'll probably get some stale cache files. |
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|
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Loops: |
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|
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To use a loop in your template, you can either do something like: |
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{LOOP MYLOOP} |
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this is loop {MYLOOP} |
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{!LOOP} |
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|
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If you have the loop {'MYLOOP': range(1, 10)}, then the above will print out |
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'this is loop X' 10 times. You can also use a more complex loop, say |
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'MYLOOP' is set to: |
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[{'val1': 1.1, 'val2': 1.2}, {'val1': 2.1, 'val2': '2.2'}], then |
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{LOOP MYLOOP} |
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loop values: val1 = {MYLOOP.val1}, val2 = {MYLOOP.val2} |
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{!LOOP} |
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|
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will output: |
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loop values: val1 = 1.1, val2 = 1.2 |
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loop values: val1 = 2.1, val2 = 2.2 |
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|
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|
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Ifs: |
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|
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If statements can be used as follows: |
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{IF TAG == 'value'} |
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{TAG} is equal to 'value' |
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{ELSE} |
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{TAG} is not equal to 'value' |
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{!IF} |
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|
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The currently supported operators include: |
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== != > < |
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""" |
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|
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__revision__ = '$Id$' |
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__authors__ = ["Scott Hadfield <hadfield@gentoo.org>", |
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"Ian Leitch <port001@gentoo.org>"] |
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__modulename__ = 'template' |
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|
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import os |
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import re |
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|
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ATOM = r'[\(\)\w]' |
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VAR_REGEX = r'%s+(?:\.%s+)*' % (ATOM, ATOM) |
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LITERAL_REGEX = r'"[^"]*"|"?\d+"?' |
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VAR_EXPR = r'(?:%s|%s)' % (VAR_REGEX, LITERAL_REGEX) |
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EXPR_REGEX = r'(%s) (==|!=|<|>) (%s)' % (VAR_EXPR, VAR_EXPR) |
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|
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class ParseTree: |
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"""The ParseTree object for template parse trees.""" |
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|
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def __init__(self): |
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pass |
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|
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def _find_closer(self, content, opener, closer): |
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"""Returns the index of the closing marker for this block of text. |
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|
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@param content - The block of text to work with. |
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@param opener - The opening of a block |
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@param closer - The closing of a block. |
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@return - The index at the start position of the closer. |
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|
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>>> block = '{O}{O}{O}{C}{O}{O}{C}{C}{C}{C}' |
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>>> ParseTree()._find_closer(block, '{O}', '{C}') |
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27 |
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>>> block = '{O}{O}{C}{O}{C}{C}' |
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>>> ParseTree()._find_closer(block, '{O}', '{C}') |
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15 |
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""" |
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|
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end = 0 |
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pos = len(opener) |
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open_count = 1 |
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while True: |
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start = content.find(opener, pos) |
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end = content.find(closer, pos) |
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if end == -1: |
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raise TemplateError("Could not locate end of block: %s" % |
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content) |
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if end < start or start == -1: |
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open_count -= 1 |
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pos = end + len(closer) |
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else: |
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open_count += 1 |
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pos = start + len(opener) |
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if open_count == 0: |
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break |
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|
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return end |
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|
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def _min(self, val1, val2): |
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"""Same as builtin min, but doesn't accept None as the min.""" |
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|
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if val1 is None or val2 is None: |
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return val1 or val2 |
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return min(val1, val2) |
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|
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def _split_if(self, if_block): |
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"""Break an if block into it's pre- and post-else parts. |
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|
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>>> block = 'b1{IF X == Y}a1{ELSE}a2{!IF}{ELSE}b2{IF W == Y}' + \ |
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'c1{ELSE}c2{!IF}{!IF}' |
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>>> ParseTree()._split_if(block) |
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('b1{IF X == Y}a1{ELSE}a2{!IF}', 'b2{IF W == Y}c1{ELSE}c2{!IF}') |
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""" |
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|
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re_if = re.compile(r'(?s)\{IF (%s)\}' % EXPR_REGEX) |
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|
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# Mark all nested if blocks |
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if_blocks = [] |
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start_if = re_if.search(if_block) |
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if start_if is None: |
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pos = 0 |
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else: |
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pos = start_if.start() - 1 |
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|
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while True: |
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next_if = re_if.search(if_block, pos) |
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if next_if is None: |
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break |
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|
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close_index = self._find_closer(if_block[next_if.start():], |
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"{IF ", "{!IF}") |
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pos += close_index + len("{!IF}") |
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if_blocks.append((next_if.start(), pos)) |
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|
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pos = 0 |
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while True: |
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else_index = if_block.find("{ELSE}", pos) |
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if else_index == -1: |
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else_index = len(if_block) |
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break |
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elif self._value_outside_of(else_index, if_blocks): |
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break |
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else: |
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pos += else_index + len("{ELSE}") |
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|
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if_block = if_block[:-len("{!IF}")] |
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content_block = if_block[:else_index] |
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else_block = if_block[else_index + len("{ELSE}"):] |
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|
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return content_block, else_block |
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|
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def _value_outside_of(self, index, val_list): |
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"""Returns true if index doesn't fall within any of the val_list pairs. |
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|
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>>> ParseTree()._value_outside_of(0, ((1, 3), (7, 70), (75, 80))) |
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True |
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>>> ParseTree()._value_outside_of(1, ((1, 3), (7, 70), (75, 80))) |
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False |
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>>> ParseTree()._value_outside_of(5, ((1, 3), (7, 70), (75, 80))) |
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True |
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>>> ParseTree()._value_outside_of(65, ((0, 3), (7, 70), (75, 80))) |
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False |
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>>> ParseTree()._value_outside_of(70, ((0, 3), (7, 70), (75, 80))) |
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False |
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>>> ParseTree()._value_outside_of(88, ((0, 3), (7, 70), (75, 80))) |
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True |
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""" |
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for val_pair in val_list: |
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if index >= val_pair[0] and index <= val_pair[1]: |
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return False |
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return True |
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|
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def parse(self, content): |
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"""Parses 'content' into a parse tree. |
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|
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@param content - Plain text string. |
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@result - A parse tree representing the template. |
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""" |
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|
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pos = 0 |
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parse_tree = {} |
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|
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re_var = re.compile(r'\{((?:%s)+)\}' % VAR_REGEX) |
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re_cmd = re.compile(r'(?s)\{(INCLUDE) ([^\}]+)\}') |
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re_loop = re.compile(r'(?s)\{LOOP (%s)\}' % VAR_REGEX) |
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re_if = re.compile(r'(?s)\{IF (%s)\}' % EXPR_REGEX) |
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|
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# First things first: strip out any comments. |
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content = re.sub(r'(?s)\{\*.*?\*\}', '', content) |
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|
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while pos < len(content): |
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next = None |
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next_var = re_var.search(content, pos) |
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next_cmd = re_cmd.search(content, pos) |
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next_loop = re_loop.search(content, pos) |
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next_if = re_if.search(content, pos) |
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|
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if next_var is not None: |
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next = next_var.start() |
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if next_cmd is not None: |
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next = self._min(next, next_cmd.start()) |
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if next_loop is not None: |
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next = self._min(next, next_loop.start()) |
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if next_if is not None: |
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next = self._min(next, next_if.start()) |
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|
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if next is not None and next != pos: |
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parse_tree[pos] = content[pos:next] |
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pos = next |
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|
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elif next_var is not None and next == next_var.start(): |
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parse_tree[pos] = {'VAR': next_var.group(1)} |
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pos = next_var.end() |
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|
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elif next_cmd is not None and next == next_cmd.start(): |
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parse_tree[pos] = {"CMD": |
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(next_cmd.group(1), next_cmd.group(2))} |
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pos = next_cmd.end() |
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|
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elif next_loop is not None and next == next_loop.start(): |
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close_index = self._find_closer(content[next:], |
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"{LOOP ", "{!LOOP}") |
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block = content[next + len(next_loop.group()): |
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next + close_index] |
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parse_tree[pos] = {'LOOP': |
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self.parse_loop(next_loop.group(1), block)} |
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pos = next + close_index + len("{!LOOP}") |
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|
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elif next_if is not None and next == next_if.start(): |
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close_index = self._find_closer(content[next:], |
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"{IF ", "{!IF}") |
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block = content[next + len(next_if.group()): |
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next + close_index + len("{!IF}")] |
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parse_tree[pos] = {'IF': |
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self.parse_if(next_if.group(1), block)} |
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pos = next + close_index + len("{!IF}") |
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|
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else: |
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parse_tree[pos] = content[pos:] |
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break |
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|
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return parse_tree |
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|
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def parse_loop(self, variable, content): |
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"""Returns the parse tree for a loop.""" |
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return {'VAR': variable, |
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'CONTENT': self.parse(content)} |
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|
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def parse_if(self, expression, content): |
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"""Returns the parse tree for an if statement.""" |
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|
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if_content, else_content = self._split_if(content) |
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|
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return {'EXPR': expression, |
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'IF_CONTENT': self.parse(if_content), |
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'ELSE_CONTENT': self.parse(else_content)} |
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|
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def unparse(self, parse_tree): |
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"""Converts a parse tree to it's plain text representation. |
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|
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No interpretation. Mostly useful for debugging. |
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""" |
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|
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result = "" |
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places = parse_tree.keys() |
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places.sort() |
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|
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for place in places: |
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if type(parse_tree[place]) is str: |
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result += parse_tree[place] |
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|
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elif parse_tree[place].keys()[0] == "VAR": |
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result += '{' + parse_tree[place]["VAR"] + '}' |
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|
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elif parse_tree[place].keys()[0] == "CMD": |
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result += '{' + parse_tree[place]["CMD"][0] + \ |
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parse_tree[place]["CMD"][1] + '}' |
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|
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elif parse_tree[place].keys()[0] == "LOOP": |
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result += '{LOOP ' + parse_tree[place]["LOOP"]["VAR"] + '}' |
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result += self.unparse(parse_tree[place]["LOOP"]["CONTENT"]) |
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result += '{!LOOP}' |
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|
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elif parse_tree[place].keys()[0] == "IF": |
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result += '{IF ' + parse_tree[place]["IF"]["EXPR"] + '}' |
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result += self.unparse(parse_tree[place]["IF"]["IF_CONTENT"]) |
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if parse_tree[place]["IF"]["ELSE_CONTENT"] != {}: |
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result += ( |
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'{ELSE}' + |
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self.unparse(parse_tree[place]["IF"]["ELSE_CONTENT"])) |
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result += '{!IF}' |
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|
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return result |
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|
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|
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class Template: |
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"""Template handler class. Gets a template parse tree and compiles it.""" |
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|
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def __init__(self, template = ""): |
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|
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self._template = template |
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self._terms = {} |
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self._output = "" |
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self.__compiled = False |
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|
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# Where is the cache located? |
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self.cache_dir = "tmpl_cache/" |
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|
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# Do you want to use template caching? |
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self.use_cache = False |
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|
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def _call_function(self, funcs, value, var): |
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"""Returns the result of running 'func' on 'value'.""" |
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|
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retval = value |
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for func in funcs: |
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|
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if func == "len": |
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if retval is None: |
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retval = 0 |
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continue |
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|
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try: |
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retval = len(retval) |
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except TypeError: |
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retval = len(str(retval)) |
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|
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if func == "iterator": |
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"""Returns the current index in loop iterations.""" |
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if var.rfind('.') == -1: |
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retval = None |
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else: |
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retval = var[(var.rfind('.')) + 1:] |
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|
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if func == "is_odd": |
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if int(retval) % 2 == 1: |
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retval = 1 |
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else: |
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retval = 0 |
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|
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if func == "isset": |
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if value == "" or value == "{%s}" % var: |
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retval = 0 |
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else: |
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retval = 1 |
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|
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return retval |
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|
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def _split_functions(self, var): |
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"""Seperate the function calls from the variable they're acting on. |
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|
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>>> Template()._split_functions('SIMPLE_VAR') |
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([], 'SIMPLE_VAR') |
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>>> Template()._split_functions('func1(SIMPLE_LOOP)') |
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(['func1'], 'SIMPLE_LOOP') |
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>>> Template()._split_functions('func1(func2(SIMPLE_LOOP))') |
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(['func2', 'func1'], 'SIMPLE_LOOP') |
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""" |
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|
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funcs = [] |
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|
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while var.find('(') != -1: |
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func, var = re.search(r'([^\(]+)\((.+)\)', var).groups() |
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funcs.insert(0, func) |
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|
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return funcs, var |
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|
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def _get_value(self, var): |
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"""Returns the stored parameter matching the description of 'var'. |
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|
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>>> tmpl = Template() |
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>>> tmpl._terms = {'test_term': 'j', 'list1': {'list2': 'found me'}} |
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>>> tmpl._get_value('test_term') |
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'j' |
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>>> tmpl._get_value('list1.list2') |
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'found me' |
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""" |
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|
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# Is this a function call? Break out the actual variable if it is. |
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funcs, var = self._split_functions(var) |
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|
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# Convert the template parameter into a python interpretable variable. |
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pyvar = self._term_to_pyvar(var) |
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|
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try: |
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# Make sure no evilness can get passed to the eval |
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if re.sub(r'[\w\'"\[\]]', "", pyvar) != "": |
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raise ValueError, "Can't interpret '%s'!" % pyvar |
| 397 |
|
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value = eval("self._terms" + pyvar) |
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|
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except KeyError: |
| 401 |
if not __debug__: |
| 402 |
value = "" |
| 403 |
if len(funcs): |
| 404 |
value = '{%s(%s)}' % (funcs, self._pyvar_to_term(pyvar)) |
| 405 |
value = '{%s}' % self._pyvar_to_term(pyvar) |
| 406 |
|
| 407 |
if len(funcs): |
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value = self._call_function(funcs, value, var) |
| 409 |
|
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return value |
| 411 |
|
| 412 |
def _read(self): |
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"""Load the content of the template file and return the contents.""" |
| 414 |
|
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try: |
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return open(self._template, "r").read() |
| 417 |
except IOError, errmsg: |
| 418 |
raise TemplateError("Caught an IOError exception: '%s'" % errmsg) |
| 419 |
|
| 420 |
def _read_include(self, include): |
| 421 |
"""Returns the contents of the specified INCLUDE.""" |
| 422 |
|
| 423 |
# Path is relative. So use this template's path as the basedir. |
| 424 |
path = os.path.dirname(self._template) + "/" |
| 425 |
|
| 426 |
return open(path + include, "r").read() |
| 427 |
|
| 428 |
def _check_cache(self, digest): |
| 429 |
"""Verify the existence of the cache with digest 'digest'.""" |
| 430 |
|
| 431 |
if not os.path.exists(self.cache_dir): |
| 432 |
raise TemplateError('Template cache directory missing') |
| 433 |
|
| 434 |
for filename in os.listdir(self.cache_dir): |
| 435 |
if filename.endswith('.cache'): |
| 436 |
if digest == filename.split('.')[0]: |
| 437 |
return True |
| 438 |
|
| 439 |
return False |
| 440 |
|
| 441 |
def _read_cache(self, digest): |
| 442 |
"""Load the cached template and store it in _output.""" |
| 443 |
|
| 444 |
try: |
| 445 |
readfd = open( |
| 446 |
os.path.join(self.cache_dir, digest + '.cache'), 'r') |
| 447 |
readfd.close() |
| 448 |
return readfd.read() |
| 449 |
|
| 450 |
except IOError, errmsg: |
| 451 |
raise TemplateError('Failed to open template cache file', |
| 452 |
errmsg) |
| 453 |
|
| 454 |
def _write_cache(self, digest): |
| 455 |
"""Write the cached file to disk.""" |
| 456 |
|
| 457 |
try: |
| 458 |
writefd = open( |
| 459 |
os.path.join(self.cache_dir, digest + '.cache'), 'w') |
| 460 |
writefd.close() |
| 461 |
writefd.write(self._output) |
| 462 |
|
| 463 |
except IOError, err: |
| 464 |
raise TemplateError('Template cache write failed', err) |
| 465 |
|
| 466 |
def _term_to_pyvar(self, var): |
| 467 |
"""Converts a 'dotted' variable to a python variable. |
| 468 |
|
| 469 |
>>> Template()._term_to_pyvar('var1') |
| 470 |
"['var1']" |
| 471 |
>>> Template()._term_to_pyvar('var1.innervar') |
| 472 |
"['var1']['innervar']" |
| 473 |
>>> Template()._term_to_pyvar('var1.inner.very_inner') |
| 474 |
"['var1']['inner']['very_inner']" |
| 475 |
>>> Template()._term_to_pyvar('var1.0') |
| 476 |
"['var1'][0]" |
| 477 |
""" |
| 478 |
|
| 479 |
pyvar = "" |
| 480 |
parts = var.split(".") |
| 481 |
for part in parts: |
| 482 |
try: |
| 483 |
inner_val = "[%i]" % int(part) |
| 484 |
except ValueError: |
| 485 |
inner_val = "['%s']" % part |
| 486 |
pyvar += inner_val |
| 487 |
|
| 488 |
return pyvar |
| 489 |
|
| 490 |
def _pyvar_to_term(self, var): |
| 491 |
"""Converts a python variable to a 'dotted' variable for template use. |
| 492 |
|
| 493 |
>>> Template()._pyvar_to_term("['var1']") |
| 494 |
'var1' |
| 495 |
>>> Template()._pyvar_to_term("['var1']['innervar']") |
| 496 |
'var1.innervar' |
| 497 |
>>> Template()._pyvar_to_term("['var1']['inner']['very_inner']") |
| 498 |
'var1.inner.very_inner' |
| 499 |
>>> Template()._pyvar_to_term("['var1'][0]") |
| 500 |
'var1.0' |
| 501 |
""" |
| 502 |
|
| 503 |
# Chop off the start and end [, ], and then replace the rest with .'s |
| 504 |
var = var[1:-1] |
| 505 |
var = var.replace("][", '.') |
| 506 |
var = var.replace("'", "") |
| 507 |
return var |
| 508 |
|
| 509 |
def _value_of(self, var): |
| 510 |
"""Returns the literal value of any variable or literal.""" |
| 511 |
|
| 512 |
# If it's surrounded by quotes or all digits then we have a literal |
| 513 |
if ((var[0] == "\"" and var[-1] == "\"") or |
| 514 |
re.match(r'^\d*$', var) is not None): |
| 515 |
return var.strip("\"") |
| 516 |
|
| 517 |
else: |
| 518 |
return self._get_value(var) |
| 519 |
|
| 520 |
def evaluate_expression(self, expr): |
| 521 |
"""Evaluate any boolean expressions |
| 522 |
|
| 523 |
expr should contain an operator (i.e. ==, <, >, !=) and this |
| 524 |
function will return True or False. |
| 525 |
""" |
| 526 |
|
| 527 |
match = re.search(EXPR_REGEX, expr) |
| 528 |
if match is None: |
| 529 |
raise TemplateError("Error parsing IF expression.") |
| 530 |
|
| 531 |
lhs = self._value_of(match.group(1)) |
| 532 |
rhs = self._value_of(match.group(3)) |
| 533 |
oper = match.group(2) |
| 534 |
|
| 535 |
if re.sub(r'[0-9]', "", str(lhs)) == "" and lhs != "": |
| 536 |
lhs = int(lhs) |
| 537 |
if re.sub(r'[0-9]', "", str(rhs)) == "" and rhs != "": |
| 538 |
rhs = int(rhs) |
| 539 |
|
| 540 |
if oper == "==" and lhs == rhs: |
| 541 |
return True |
| 542 |
elif oper == "<" and lhs < rhs: |
| 543 |
return True |
| 544 |
elif oper == ">" and lhs > rhs: |
| 545 |
return True |
| 546 |
elif oper == "!=" and lhs != rhs: |
| 547 |
return True |
| 548 |
|
| 549 |
return False |
| 550 |
|
| 551 |
def interpret(self, parse_tree): |
| 552 |
"""Interpret the given parse tree. |
| 553 |
|
| 554 |
This functions returns a fully evaluated template based on the |
| 555 |
parameters that were set. |
| 556 |
""" |
| 557 |
|
| 558 |
result = "" |
| 559 |
places = parse_tree.keys() |
| 560 |
places.sort() |
| 561 |
|
| 562 |
for place in places: |
| 563 |
|
| 564 |
if type(parse_tree[place]) is str: |
| 565 |
result += parse_tree[place] |
| 566 |
|
| 567 |
elif parse_tree[place].keys()[0] == "VAR": |
| 568 |
result += self.interpret_var(parse_tree[place]["VAR"]) |
| 569 |
|
| 570 |
elif parse_tree[place].keys()[0] == "CMD": |
| 571 |
result += self.interpret_cmd(parse_tree[place]["CMD"]) |
| 572 |
|
| 573 |
elif parse_tree[place].keys()[0] == "LOOP": |
| 574 |
result += self.interpret_loop( |
| 575 |
parse_tree[place]["LOOP"]["VAR"], |
| 576 |
parse_tree[place]["LOOP"]["CONTENT"]) |
| 577 |
|
| 578 |
elif parse_tree[place].keys()[0] == "IF": |
| 579 |
result += self.interpret_if( |
| 580 |
parse_tree[place]["IF"]["EXPR"], |
| 581 |
parse_tree[place]["IF"]["IF_CONTENT"], |
| 582 |
parse_tree[place]["IF"]["ELSE_CONTENT"]) |
| 583 |
|
| 584 |
return result |
| 585 |
|
| 586 |
def interpret_var(self, var): |
| 587 |
"""Returns the value if self._terms[var] if it exists.""" |
| 588 |
|
| 589 |
retval = self._get_value(var) |
| 590 |
return str(retval) |
| 591 |
|
| 592 |
def interpret_cmd(self, (cmd, parameters)): |
| 593 |
"""Performs a specific action for each possible command. |
| 594 |
|
| 595 |
Command | Action |
| 596 |
INCLUDE | Loads the specified include file. |
| 597 |
""" |
| 598 |
|
| 599 |
if cmd == "INCLUDE": |
| 600 |
return self.interpret( |
| 601 |
ParseTree().parse(self._read_include(parameters))) |
| 602 |
return "" |
| 603 |
|
| 604 |
def interpret_loop(self, var, content): |
| 605 |
"""Interprets a loop. |
| 606 |
|
| 607 |
This function works by [probably inefficiently] by first unparsing |
| 608 |
the content block, replacing all variables with a way to properly |
| 609 |
reference their actual value, and re-parsing it. For example, if the |
| 610 |
loop is {THE_LOOP} and it has a value, {THE_LOOP.myvalue}, on the |
| 611 |
first iteration of the loop, {THE_LOOP.myvalue} will be altered to |
| 612 |
{THE_LOOP.0.myvalue} so as to reference the first object in |
| 613 |
THE_LOOP. |
| 614 |
""" |
| 615 |
|
| 616 |
loop_val = self._get_value(var) |
| 617 |
loop_content = "" |
| 618 |
if type(loop_val) in (list, tuple): |
| 619 |
for i in range(0, len(loop_val)): |
| 620 |
tmp = ParseTree().unparse(content) |
| 621 |
tmp = re.sub(r'(\{[^\}]*\b)%s(\b[^\}]*\})' % var, |
| 622 |
r'\1%s.%i\2' % (var, i), tmp) |
| 623 |
loop_content += self.interpret(ParseTree().parse(tmp)) |
| 624 |
|
| 625 |
return loop_content |
| 626 |
|
| 627 |
def interpret_if(self, expr, if_content, else_content): |
| 628 |
"""Interprets the two 'winning' half of the loop.""" |
| 629 |
|
| 630 |
if self.evaluate_expression(expr): |
| 631 |
return self.interpret(if_content) |
| 632 |
else: |
| 633 |
return self.interpret(else_content) |
| 634 |
|
| 635 |
def compile(self): |
| 636 |
"""Processes the template and save it in our self._output variable.""" |
| 637 |
|
| 638 |
import md5 |
| 639 |
import thread |
| 640 |
|
| 641 |
if self.use_cache: |
| 642 |
digest_str = str(self._template) + str(self._terms) |
| 643 |
digest = md5.new(digest_str).hexdigest() |
| 644 |
|
| 645 |
if self._check_cache(digest): |
| 646 |
self._output = self._read_cache(digest) |
| 647 |
|
| 648 |
else: |
| 649 |
self._output = self.interpret(ParseTree().parse(self._read())) |
| 650 |
if self.use_cache: |
| 651 |
thread.start_new_thread(self._write_cache, (digest,)) |
| 652 |
|
| 653 |
self.__compiled = True |
| 654 |
|
| 655 |
def output(self): |
| 656 |
"""Returns the resulting template.""" |
| 657 |
|
| 658 |
if not self.__compiled: |
| 659 |
self.compile() |
| 660 |
|
| 661 |
return self._output |
| 662 |
|
| 663 |
def param(self, key, value): |
| 664 |
"""Add the specified parameter to our parameter list. |
| 665 |
|
| 666 |
This method is here for backwards compatibility only. |
| 667 |
""" |
| 668 |
self._terms.update({key: value}) |
| 669 |
|
| 670 |
def params(self, terms): |
| 671 |
"""Add a dict of values to our terms.""" |
| 672 |
self._terms.update(terms) |
| 673 |
|
| 674 |
def reset(self): |
| 675 |
"""Reset this template object.""" |
| 676 |
self.__compiled = False |
| 677 |
self._output = "" |
| 678 |
self._terms = {} |
| 679 |
|
| 680 |
def set_template(self, template): |
| 681 |
"""Allow the user to manually set the template.""" |
| 682 |
self.__compiled = False |
| 683 |
self._output = "" |
| 684 |
self._template = template |
| 685 |
|
| 686 |
|
| 687 |
class TemplateError(Exception): |
| 688 |
"""The base exception for any template errors""" |
| 689 |
pass |
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