--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/app/django/template/defaulttags.py Fri Jul 18 18:22:23 2008 +0000
@@ -0,0 +1,1103 @@
+"""Default tags used by the template system, available to all templates."""
+
+import sys
+import re
+from itertools import cycle as itertools_cycle
+try:
+ reversed
+except NameError:
+ from django.utils.itercompat import reversed # Python 2.3 fallback
+
+from django.template import Node, NodeList, Template, Context, Variable
+from django.template import TemplateSyntaxError, VariableDoesNotExist, BLOCK_TAG_START, BLOCK_TAG_END, VARIABLE_TAG_START, VARIABLE_TAG_END, SINGLE_BRACE_START, SINGLE_BRACE_END, COMMENT_TAG_START, COMMENT_TAG_END
+from django.template import get_library, Library, InvalidTemplateLibrary
+from django.conf import settings
+from django.utils.encoding import smart_str, smart_unicode
+from django.utils.itercompat import groupby
+from django.utils.safestring import mark_safe
+
+register = Library()
+
+class AutoEscapeControlNode(Node):
+ """Implements the actions of the autoescape tag."""
+ def __init__(self, setting, nodelist):
+ self.setting, self.nodelist = setting, nodelist
+
+ def render(self, context):
+ old_setting = context.autoescape
+ context.autoescape = self.setting
+ output = self.nodelist.render(context)
+ context.autoescape = old_setting
+ if self.setting:
+ return mark_safe(output)
+ else:
+ return output
+
+class CommentNode(Node):
+ def render(self, context):
+ return ''
+
+class CycleNode(Node):
+ def __init__(self, cyclevars, variable_name=None):
+ self.cycle_iter = itertools_cycle(cyclevars)
+ self.variable_name = variable_name
+
+ def render(self, context):
+ value = self.cycle_iter.next()
+ value = Variable(value).resolve(context)
+ if self.variable_name:
+ context[self.variable_name] = value
+ return value
+
+class DebugNode(Node):
+ def render(self, context):
+ from pprint import pformat
+ output = [pformat(val) for val in context]
+ output.append('\n\n')
+ output.append(pformat(sys.modules))
+ return ''.join(output)
+
+class FilterNode(Node):
+ def __init__(self, filter_expr, nodelist):
+ self.filter_expr, self.nodelist = filter_expr, nodelist
+
+ def render(self, context):
+ output = self.nodelist.render(context)
+ # Apply filters.
+ context.update({'var': output})
+ filtered = self.filter_expr.resolve(context)
+ context.pop()
+ return filtered
+
+class FirstOfNode(Node):
+ def __init__(self, vars):
+ self.vars = map(Variable, vars)
+
+ def render(self, context):
+ for var in self.vars:
+ try:
+ value = var.resolve(context)
+ except VariableDoesNotExist:
+ continue
+ if value:
+ return smart_unicode(value)
+ return u''
+
+class ForNode(Node):
+ def __init__(self, loopvars, sequence, is_reversed, nodelist_loop):
+ self.loopvars, self.sequence = loopvars, sequence
+ self.is_reversed = is_reversed
+ self.nodelist_loop = nodelist_loop
+
+ def __repr__(self):
+ reversed_text = self.is_reversed and ' reversed' or ''
+ return "<For Node: for %s in %s, tail_len: %d%s>" % \
+ (', '.join(self.loopvars), self.sequence, len(self.nodelist_loop),
+ reversed_text)
+
+ def __iter__(self):
+ for node in self.nodelist_loop:
+ yield node
+
+ def get_nodes_by_type(self, nodetype):
+ nodes = []
+ if isinstance(self, nodetype):
+ nodes.append(self)
+ nodes.extend(self.nodelist_loop.get_nodes_by_type(nodetype))
+ return nodes
+
+ def render(self, context):
+ nodelist = NodeList()
+ if 'forloop' in context:
+ parentloop = context['forloop']
+ else:
+ parentloop = {}
+ context.push()
+ try:
+ values = self.sequence.resolve(context, True)
+ except VariableDoesNotExist:
+ values = []
+ if values is None:
+ values = []
+ if not hasattr(values, '__len__'):
+ values = list(values)
+ len_values = len(values)
+ if self.is_reversed:
+ values = reversed(values)
+ unpack = len(self.loopvars) > 1
+ # Create a forloop value in the context. We'll update counters on each
+ # iteration just below.
+ loop_dict = context['forloop'] = {'parentloop': parentloop}
+ for i, item in enumerate(values):
+ # Shortcuts for current loop iteration number.
+ loop_dict['counter0'] = i
+ loop_dict['counter'] = i+1
+ # Reverse counter iteration numbers.
+ loop_dict['revcounter'] = len_values - i
+ loop_dict['revcounter0'] = len_values - i - 1
+ # Boolean values designating first and last times through loop.
+ loop_dict['first'] = (i == 0)
+ loop_dict['last'] = (i == len_values - 1)
+
+ if unpack:
+ # If there are multiple loop variables, unpack the item into
+ # them.
+ context.update(dict(zip(self.loopvars, item)))
+ else:
+ context[self.loopvars[0]] = item
+ for node in self.nodelist_loop:
+ nodelist.append(node.render(context))
+ if unpack:
+ # The loop variables were pushed on to the context so pop them
+ # off again. This is necessary because the tag lets the length
+ # of loopvars differ to the length of each set of items and we
+ # don't want to leave any vars from the previous loop on the
+ # context.
+ context.pop()
+ context.pop()
+ return nodelist.render(context)
+
+class IfChangedNode(Node):
+ def __init__(self, nodelist, *varlist):
+ self.nodelist = nodelist
+ self._last_seen = None
+ self._varlist = map(Variable, varlist)
+
+ def render(self, context):
+ if 'forloop' in context and context['forloop']['first']:
+ self._last_seen = None
+ try:
+ if self._varlist:
+ # Consider multiple parameters. This automatically behaves
+ # like an OR evaluation of the multiple variables.
+ compare_to = [var.resolve(context) for var in self._varlist]
+ else:
+ compare_to = self.nodelist.render(context)
+ except VariableDoesNotExist:
+ compare_to = None
+
+ if compare_to != self._last_seen:
+ firstloop = (self._last_seen == None)
+ self._last_seen = compare_to
+ context.push()
+ context['ifchanged'] = {'firstloop': firstloop}
+ content = self.nodelist.render(context)
+ context.pop()
+ return content
+ else:
+ return ''
+
+class IfEqualNode(Node):
+ def __init__(self, var1, var2, nodelist_true, nodelist_false, negate):
+ self.var1, self.var2 = Variable(var1), Variable(var2)
+ self.nodelist_true, self.nodelist_false = nodelist_true, nodelist_false
+ self.negate = negate
+
+ def __repr__(self):
+ return "<IfEqualNode>"
+
+ def render(self, context):
+ try:
+ val1 = self.var1.resolve(context)
+ except VariableDoesNotExist:
+ val1 = None
+ try:
+ val2 = self.var2.resolve(context)
+ except VariableDoesNotExist:
+ val2 = None
+ if (self.negate and val1 != val2) or (not self.negate and val1 == val2):
+ return self.nodelist_true.render(context)
+ return self.nodelist_false.render(context)
+
+class IfNode(Node):
+ def __init__(self, bool_exprs, nodelist_true, nodelist_false, link_type):
+ self.bool_exprs = bool_exprs
+ self.nodelist_true, self.nodelist_false = nodelist_true, nodelist_false
+ self.link_type = link_type
+
+ def __repr__(self):
+ return "<If node>"
+
+ def __iter__(self):
+ for node in self.nodelist_true:
+ yield node
+ for node in self.nodelist_false:
+ yield node
+
+ def get_nodes_by_type(self, nodetype):
+ nodes = []
+ if isinstance(self, nodetype):
+ nodes.append(self)
+ nodes.extend(self.nodelist_true.get_nodes_by_type(nodetype))
+ nodes.extend(self.nodelist_false.get_nodes_by_type(nodetype))
+ return nodes
+
+ def render(self, context):
+ if self.link_type == IfNode.LinkTypes.or_:
+ for ifnot, bool_expr in self.bool_exprs:
+ try:
+ value = bool_expr.resolve(context, True)
+ except VariableDoesNotExist:
+ value = None
+ if (value and not ifnot) or (ifnot and not value):
+ return self.nodelist_true.render(context)
+ return self.nodelist_false.render(context)
+ else:
+ for ifnot, bool_expr in self.bool_exprs:
+ try:
+ value = bool_expr.resolve(context, True)
+ except VariableDoesNotExist:
+ value = None
+ if not ((value and not ifnot) or (ifnot and not value)):
+ return self.nodelist_false.render(context)
+ return self.nodelist_true.render(context)
+
+ class LinkTypes:
+ and_ = 0,
+ or_ = 1
+
+class RegroupNode(Node):
+ def __init__(self, target, expression, var_name):
+ self.target, self.expression = target, expression
+ self.var_name = var_name
+
+ def render(self, context):
+ obj_list = self.target.resolve(context, True)
+ if obj_list == None:
+ # target variable wasn't found in context; fail silently.
+ context[self.var_name] = []
+ return ''
+ # List of dictionaries in the format:
+ # {'grouper': 'key', 'list': [list of contents]}.
+ context[self.var_name] = [
+ {'grouper': key, 'list': list(val)}
+ for key, val in
+ groupby(obj_list, lambda v, f=self.expression.resolve: f(v, True))
+ ]
+ return ''
+
+def include_is_allowed(filepath):
+ for root in settings.ALLOWED_INCLUDE_ROOTS:
+ if filepath.startswith(root):
+ return True
+ return False
+
+class SsiNode(Node):
+ def __init__(self, filepath, parsed):
+ self.filepath, self.parsed = filepath, parsed
+
+ def render(self, context):
+ if not include_is_allowed(self.filepath):
+ if settings.DEBUG:
+ return "[Didn't have permission to include file]"
+ else:
+ return '' # Fail silently for invalid includes.
+ try:
+ fp = open(self.filepath, 'r')
+ output = fp.read()
+ fp.close()
+ except IOError:
+ output = ''
+ if self.parsed:
+ try:
+ t = Template(output, name=self.filepath)
+ return t.render(context)
+ except TemplateSyntaxError, e:
+ if settings.DEBUG:
+ return "[Included template had syntax error: %s]" % e
+ else:
+ return '' # Fail silently for invalid included templates.
+ return output
+
+class LoadNode(Node):
+ def render(self, context):
+ return ''
+
+class NowNode(Node):
+ def __init__(self, format_string):
+ self.format_string = format_string
+
+ def render(self, context):
+ from datetime import datetime
+ from django.utils.dateformat import DateFormat
+ df = DateFormat(datetime.now())
+ return df.format(self.format_string)
+
+class SpacelessNode(Node):
+ def __init__(self, nodelist):
+ self.nodelist = nodelist
+
+ def render(self, context):
+ from django.utils.html import strip_spaces_between_tags
+ return strip_spaces_between_tags(self.nodelist.render(context).strip())
+
+class TemplateTagNode(Node):
+ mapping = {'openblock': BLOCK_TAG_START,
+ 'closeblock': BLOCK_TAG_END,
+ 'openvariable': VARIABLE_TAG_START,
+ 'closevariable': VARIABLE_TAG_END,
+ 'openbrace': SINGLE_BRACE_START,
+ 'closebrace': SINGLE_BRACE_END,
+ 'opencomment': COMMENT_TAG_START,
+ 'closecomment': COMMENT_TAG_END,
+ }
+
+ def __init__(self, tagtype):
+ self.tagtype = tagtype
+
+ def render(self, context):
+ return self.mapping.get(self.tagtype, '')
+
+class URLNode(Node):
+ def __init__(self, view_name, args, kwargs):
+ self.view_name = view_name
+ self.args = args
+ self.kwargs = kwargs
+
+ def render(self, context):
+ from django.core.urlresolvers import reverse, NoReverseMatch
+ args = [arg.resolve(context) for arg in self.args]
+ kwargs = dict([(smart_str(k,'ascii'), v.resolve(context))
+ for k, v in self.kwargs.items()])
+ try:
+ return reverse(self.view_name, args=args, kwargs=kwargs)
+ except NoReverseMatch:
+ try:
+ project_name = settings.SETTINGS_MODULE.split('.')[0]
+ return reverse(project_name + '.' + self.view_name,
+ args=args, kwargs=kwargs)
+ except NoReverseMatch:
+ return ''
+
+class WidthRatioNode(Node):
+ def __init__(self, val_expr, max_expr, max_width):
+ self.val_expr = val_expr
+ self.max_expr = max_expr
+ self.max_width = max_width
+
+ def render(self, context):
+ try:
+ value = self.val_expr.resolve(context)
+ maxvalue = self.max_expr.resolve(context)
+ except VariableDoesNotExist:
+ return ''
+ try:
+ value = float(value)
+ maxvalue = float(maxvalue)
+ ratio = (value / maxvalue) * int(self.max_width)
+ except (ValueError, ZeroDivisionError):
+ return ''
+ return str(int(round(ratio)))
+
+class WithNode(Node):
+ def __init__(self, var, name, nodelist):
+ self.var = var
+ self.name = name
+ self.nodelist = nodelist
+
+ def __repr__(self):
+ return "<WithNode>"
+
+ def render(self, context):
+ val = self.var.resolve(context)
+ context.push()
+ context[self.name] = val
+ output = self.nodelist.render(context)
+ context.pop()
+ return output
+
+#@register.tag
+def autoescape(parser, token):
+ """
+ Force autoescape behaviour for this block.
+ """
+ args = token.contents.split()
+ if len(args) != 2:
+ raise TemplateSyntaxError("'Autoescape' tag requires exactly one argument.")
+ arg = args[1]
+ if arg not in (u'on', u'off'):
+ raise TemplateSyntaxError("'Autoescape' argument should be 'on' or 'off'")
+ nodelist = parser.parse(('endautoescape',))
+ parser.delete_first_token()
+ return AutoEscapeControlNode((arg == 'on'), nodelist)
+autoescape = register.tag(autoescape)
+
+#@register.tag
+def comment(parser, token):
+ """
+ Ignores everything between ``{% comment %}`` and ``{% endcomment %}``.
+ """
+ parser.skip_past('endcomment')
+ return CommentNode()
+comment = register.tag(comment)
+
+#@register.tag
+def cycle(parser, token):
+ """
+ Cycles among the given strings each time this tag is encountered.
+
+ Within a loop, cycles among the given strings each time through
+ the loop::
+
+ {% for o in some_list %}
+ <tr class="{% cycle 'row1' 'row2' %}">
+ ...
+ </tr>
+ {% endfor %}
+
+ Outside of a loop, give the values a unique name the first time you call
+ it, then use that name each sucessive time through::
+
+ <tr class="{% cycle 'row1' 'row2' 'row3' as rowcolors %}">...</tr>
+ <tr class="{% cycle rowcolors %}">...</tr>
+ <tr class="{% cycle rowcolors %}">...</tr>
+
+ You can use any number of values, seperated by spaces. Commas can also
+ be used to separate values; if a comma is used, the cycle values are
+ interpreted as literal strings.
+ """
+
+ # Note: This returns the exact same node on each {% cycle name %} call;
+ # that is, the node object returned from {% cycle a b c as name %} and the
+ # one returned from {% cycle name %} are the exact same object. This
+ # shouldn't cause problems (heh), but if it does, now you know.
+ #
+ # Ugly hack warning: this stuffs the named template dict into parser so
+ # that names are only unique within each template (as opposed to using
+ # a global variable, which would make cycle names have to be unique across
+ # *all* templates.
+
+ args = token.split_contents()
+
+ if len(args) < 2:
+ raise TemplateSyntaxError("'cycle' tag requires at least two arguments")
+
+ if ',' in args[1]:
+ # Backwards compatibility: {% cycle a,b %} or {% cycle a,b as foo %}
+ # case.
+ args[1:2] = ['"%s"' % arg for arg in args[1].split(",")]
+
+ if len(args) == 2:
+ # {% cycle foo %} case.
+ name = args[1]
+ if not hasattr(parser, '_namedCycleNodes'):
+ raise TemplateSyntaxError("No named cycles in template."
+ " '%s' is not defined" % name)
+ if not name in parser._namedCycleNodes:
+ raise TemplateSyntaxError("Named cycle '%s' does not exist" % name)
+ return parser._namedCycleNodes[name]
+
+ if len(args) > 4 and args[-2] == 'as':
+ name = args[-1]
+ node = CycleNode(args[1:-2], name)
+ if not hasattr(parser, '_namedCycleNodes'):
+ parser._namedCycleNodes = {}
+ parser._namedCycleNodes[name] = node
+ else:
+ node = CycleNode(args[1:])
+ return node
+cycle = register.tag(cycle)
+
+def debug(parser, token):
+ """
+ Outputs a whole load of debugging information, including the current
+ context and imported modules.
+
+ Sample usage::
+
+ <pre>
+ {% debug %}
+ </pre>
+ """
+ return DebugNode()
+debug = register.tag(debug)
+
+#@register.tag(name="filter")
+def do_filter(parser, token):
+ """
+ Filters the contents of the block through variable filters.
+
+ Filters can also be piped through each other, and they can have
+ arguments -- just like in variable syntax.
+
+ Sample usage::
+
+ {% filter force_escape|lower %}
+ This text will be HTML-escaped, and will appear in lowercase.
+ {% endfilter %}
+ """
+ _, rest = token.contents.split(None, 1)
+ filter_expr = parser.compile_filter("var|%s" % (rest))
+ for func, unused in filter_expr.filters:
+ if getattr(func, '_decorated_function', func).__name__ in ('escape', 'safe'):
+ raise TemplateSyntaxError('"filter %s" is not permitted. Use the "autoescape" tag instead.' % func.__name__)
+ nodelist = parser.parse(('endfilter',))
+ parser.delete_first_token()
+ return FilterNode(filter_expr, nodelist)
+do_filter = register.tag("filter", do_filter)
+
+#@register.tag
+def firstof(parser, token):
+ """
+ Outputs the first variable passed that is not False.
+
+ Outputs nothing if all the passed variables are False.
+
+ Sample usage::
+
+ {% firstof var1 var2 var3 %}
+
+ This is equivalent to::
+
+ {% if var1 %}
+ {{ var1 }}
+ {% else %}{% if var2 %}
+ {{ var2 }}
+ {% else %}{% if var3 %}
+ {{ var3 }}
+ {% endif %}{% endif %}{% endif %}
+
+ but obviously much cleaner!
+
+ You can also use a literal string as a fallback value in case all
+ passed variables are False::
+
+ {% firstof var1 var2 var3 "fallback value" %}
+
+ """
+ bits = token.split_contents()[1:]
+ if len(bits) < 1:
+ raise TemplateSyntaxError("'firstof' statement requires at least one"
+ " argument")
+ return FirstOfNode(bits)
+firstof = register.tag(firstof)
+
+#@register.tag(name="for")
+def do_for(parser, token):
+ """
+ Loops over each item in an array.
+
+ For example, to display a list of athletes given ``athlete_list``::
+
+ <ul>
+ {% for athlete in athlete_list %}
+ <li>{{ athlete.name }}</li>
+ {% endfor %}
+ </ul>
+
+ You can loop over a list in reverse by using
+ ``{% for obj in list reversed %}``.
+
+ You can also unpack multiple values from a two-dimensional array::
+
+ {% for key,value in dict.items %}
+ {{ key }}: {{ value }}
+ {% endfor %}
+
+ The for loop sets a number of variables available within the loop:
+
+ ========================== ================================================
+ Variable Description
+ ========================== ================================================
+ ``forloop.counter`` The current iteration of the loop (1-indexed)
+ ``forloop.counter0`` The current iteration of the loop (0-indexed)
+ ``forloop.revcounter`` The number of iterations from the end of the
+ loop (1-indexed)
+ ``forloop.revcounter0`` The number of iterations from the end of the
+ loop (0-indexed)
+ ``forloop.first`` True if this is the first time through the loop
+ ``forloop.last`` True if this is the last time through the loop
+ ``forloop.parentloop`` For nested loops, this is the loop "above" the
+ current one
+ ========================== ================================================
+
+ """
+ bits = token.contents.split()
+ if len(bits) < 4:
+ raise TemplateSyntaxError("'for' statements should have at least four"
+ " words: %s" % token.contents)
+
+ is_reversed = bits[-1] == 'reversed'
+ in_index = is_reversed and -3 or -2
+ if bits[in_index] != 'in':
+ raise TemplateSyntaxError("'for' statements should use the format"
+ " 'for x in y': %s" % token.contents)
+
+ loopvars = re.sub(r' *, *', ',', ' '.join(bits[1:in_index])).split(',')
+ for var in loopvars:
+ if not var or ' ' in var:
+ raise TemplateSyntaxError("'for' tag received an invalid argument:"
+ " %s" % token.contents)
+
+ sequence = parser.compile_filter(bits[in_index+1])
+ nodelist_loop = parser.parse(('endfor',))
+ parser.delete_first_token()
+ return ForNode(loopvars, sequence, is_reversed, nodelist_loop)
+do_for = register.tag("for", do_for)
+
+def do_ifequal(parser, token, negate):
+ bits = list(token.split_contents())
+ if len(bits) != 3:
+ raise TemplateSyntaxError, "%r takes two arguments" % bits[0]
+ end_tag = 'end' + bits[0]
+ nodelist_true = parser.parse(('else', end_tag))
+ token = parser.next_token()
+ if token.contents == 'else':
+ nodelist_false = parser.parse((end_tag,))
+ parser.delete_first_token()
+ else:
+ nodelist_false = NodeList()
+ return IfEqualNode(bits[1], bits[2], nodelist_true, nodelist_false, negate)
+
+#@register.tag
+def ifequal(parser, token):
+ """
+ Outputs the contents of the block if the two arguments equal each other.
+
+ Examples::
+
+ {% ifequal user.id comment.user_id %}
+ ...
+ {% endifequal %}
+
+ {% ifnotequal user.id comment.user_id %}
+ ...
+ {% else %}
+ ...
+ {% endifnotequal %}
+ """
+ return do_ifequal(parser, token, False)
+ifequal = register.tag(ifequal)
+
+#@register.tag
+def ifnotequal(parser, token):
+ """
+ Outputs the contents of the block if the two arguments are not equal.
+ See ifequal.
+ """
+ return do_ifequal(parser, token, True)
+ifnotequal = register.tag(ifnotequal)
+
+#@register.tag(name="if")
+def do_if(parser, token):
+ """
+ The ``{% if %}`` tag evaluates a variable, and if that variable is "true"
+ (i.e. exists, is not empty, and is not a false boolean value) the contents
+ of the block are output::
+
+ {% if athlete_list %}
+ Number of athletes: {{ athlete_list|count }}
+ {% else %}
+ No athletes.
+ {% endif %}
+
+ In the above, if ``athlete_list`` is not empty, the number of athletes will
+ be displayed by the ``{{ athlete_list|count }}`` variable.
+
+ As you can see, the ``if`` tag can take an option ``{% else %}`` clause
+ that will be displayed if the test fails.
+
+ ``if`` tags may use ``or``, ``and`` or ``not`` to test a number of
+ variables or to negate a given variable::
+
+ {% if not athlete_list %}
+ There are no athletes.
+ {% endif %}
+
+ {% if athlete_list or coach_list %}
+ There are some athletes or some coaches.
+ {% endif %}
+
+ {% if athlete_list and coach_list %}
+ Both atheletes and coaches are available.
+ {% endif %}
+
+ {% if not athlete_list or coach_list %}
+ There are no athletes, or there are some coaches.
+ {% endif %}
+
+ {% if athlete_list and not coach_list %}
+ There are some athletes and absolutely no coaches.
+ {% endif %}
+
+ ``if`` tags do not allow ``and`` and ``or`` clauses with the same tag,
+ because the order of logic would be ambigous. For example, this is
+ invalid::
+
+ {% if athlete_list and coach_list or cheerleader_list %}
+
+ If you need to combine ``and`` and ``or`` to do advanced logic, just use
+ nested if tags. For example::
+
+ {% if athlete_list %}
+ {% if coach_list or cheerleader_list %}
+ We have athletes, and either coaches or cheerleaders!
+ {% endif %}
+ {% endif %}
+ """
+ bits = token.contents.split()
+ del bits[0]
+ if not bits:
+ raise TemplateSyntaxError("'if' statement requires at least one argument")
+ # Bits now looks something like this: ['a', 'or', 'not', 'b', 'or', 'c.d']
+ bitstr = ' '.join(bits)
+ boolpairs = bitstr.split(' and ')
+ boolvars = []
+ if len(boolpairs) == 1:
+ link_type = IfNode.LinkTypes.or_
+ boolpairs = bitstr.split(' or ')
+ else:
+ link_type = IfNode.LinkTypes.and_
+ if ' or ' in bitstr:
+ raise TemplateSyntaxError, "'if' tags can't mix 'and' and 'or'"
+ for boolpair in boolpairs:
+ if ' ' in boolpair:
+ try:
+ not_, boolvar = boolpair.split()
+ except ValueError:
+ raise TemplateSyntaxError, "'if' statement improperly formatted"
+ if not_ != 'not':
+ raise TemplateSyntaxError, "Expected 'not' in if statement"
+ boolvars.append((True, parser.compile_filter(boolvar)))
+ else:
+ boolvars.append((False, parser.compile_filter(boolpair)))
+ nodelist_true = parser.parse(('else', 'endif'))
+ token = parser.next_token()
+ if token.contents == 'else':
+ nodelist_false = parser.parse(('endif',))
+ parser.delete_first_token()
+ else:
+ nodelist_false = NodeList()
+ return IfNode(boolvars, nodelist_true, nodelist_false, link_type)
+do_if = register.tag("if", do_if)
+
+#@register.tag
+def ifchanged(parser, token):
+ """
+ Checks if a value has changed from the last iteration of a loop.
+
+ The 'ifchanged' block tag is used within a loop. It has two possible uses.
+
+ 1. Checks its own rendered contents against its previous state and only
+ displays the content if it has changed. For example, this displays a
+ list of days, only displaying the month if it changes::
+
+ <h1>Archive for {{ year }}</h1>
+
+ {% for date in days %}
+ {% ifchanged %}<h3>{{ date|date:"F" }}</h3>{% endifchanged %}
+ <a href="{{ date|date:"M/d"|lower }}/">{{ date|date:"j" }}</a>
+ {% endfor %}
+
+ 2. If given a variable, check whether that variable has changed.
+ For example, the following shows the date every time it changes, but
+ only shows the hour if both the hour and the date have changed::
+
+ {% for date in days %}
+ {% ifchanged date.date %} {{ date.date }} {% endifchanged %}
+ {% ifchanged date.hour date.date %}
+ {{ date.hour }}
+ {% endifchanged %}
+ {% endfor %}
+ """
+ bits = token.contents.split()
+ nodelist = parser.parse(('endifchanged',))
+ parser.delete_first_token()
+ return IfChangedNode(nodelist, *bits[1:])
+ifchanged = register.tag(ifchanged)
+
+#@register.tag
+def ssi(parser, token):
+ """
+ Outputs the contents of a given file into the page.
+
+ Like a simple "include" tag, the ``ssi`` tag includes the contents
+ of another file -- which must be specified using an absolute path --
+ in the current page::
+
+ {% ssi /home/html/ljworld.com/includes/right_generic.html %}
+
+ If the optional "parsed" parameter is given, the contents of the included
+ file are evaluated as template code, with the current context::
+
+ {% ssi /home/html/ljworld.com/includes/right_generic.html parsed %}
+ """
+ bits = token.contents.split()
+ parsed = False
+ if len(bits) not in (2, 3):
+ raise TemplateSyntaxError("'ssi' tag takes one argument: the path to"
+ " the file to be included")
+ if len(bits) == 3:
+ if bits[2] == 'parsed':
+ parsed = True
+ else:
+ raise TemplateSyntaxError("Second (optional) argument to %s tag"
+ " must be 'parsed'" % bits[0])
+ return SsiNode(bits[1], parsed)
+ssi = register.tag(ssi)
+
+#@register.tag
+def load(parser, token):
+ """
+ Loads a custom template tag set.
+
+ For example, to load the template tags in
+ ``django/templatetags/news/photos.py``::
+
+ {% load news.photos %}
+ """
+ bits = token.contents.split()
+ for taglib in bits[1:]:
+ # add the library to the parser
+ try:
+ lib = get_library("django.templatetags.%s" % taglib)
+ parser.add_library(lib)
+ except InvalidTemplateLibrary, e:
+ raise TemplateSyntaxError("'%s' is not a valid tag library: %s" %
+ (taglib, e))
+ return LoadNode()
+load = register.tag(load)
+
+#@register.tag
+def now(parser, token):
+ """
+ Displays the date, formatted according to the given string.
+
+ Uses the same format as PHP's ``date()`` function; see http://php.net/date
+ for all the possible values.
+
+ Sample usage::
+
+ It is {% now "jS F Y H:i" %}
+ """
+ bits = token.contents.split('"')
+ if len(bits) != 3:
+ raise TemplateSyntaxError, "'now' statement takes one argument"
+ format_string = bits[1]
+ return NowNode(format_string)
+now = register.tag(now)
+
+#@register.tag
+def regroup(parser, token):
+ """
+ Regroups a list of alike objects by a common attribute.
+
+ This complex tag is best illustrated by use of an example: say that
+ ``people`` is a list of ``Person`` objects that have ``first_name``,
+ ``last_name``, and ``gender`` attributes, and you'd like to display a list
+ that looks like:
+
+ * Male:
+ * George Bush
+ * Bill Clinton
+ * Female:
+ * Margaret Thatcher
+ * Colendeeza Rice
+ * Unknown:
+ * Pat Smith
+
+ The following snippet of template code would accomplish this dubious task::
+
+ {% regroup people by gender as grouped %}
+ <ul>
+ {% for group in grouped %}
+ <li>{{ group.grouper }}
+ <ul>
+ {% for item in group.list %}
+ <li>{{ item }}</li>
+ {% endfor %}
+ </ul>
+ {% endfor %}
+ </ul>
+
+ As you can see, ``{% regroup %}`` populates a variable with a list of
+ objects with ``grouper`` and ``list`` attributes. ``grouper`` contains the
+ item that was grouped by; ``list`` contains the list of objects that share
+ that ``grouper``. In this case, ``grouper`` would be ``Male``, ``Female``
+ and ``Unknown``, and ``list`` is the list of people with those genders.
+
+ Note that `{% regroup %}`` does not work when the list to be grouped is not
+ sorted by the key you are grouping by! This means that if your list of
+ people was not sorted by gender, you'd need to make sure it is sorted
+ before using it, i.e.::
+
+ {% regroup people|dictsort:"gender" by gender as grouped %}
+
+ """
+ firstbits = token.contents.split(None, 3)
+ if len(firstbits) != 4:
+ raise TemplateSyntaxError, "'regroup' tag takes five arguments"
+ target = parser.compile_filter(firstbits[1])
+ if firstbits[2] != 'by':
+ raise TemplateSyntaxError("second argument to 'regroup' tag must be 'by'")
+ lastbits_reversed = firstbits[3][::-1].split(None, 2)
+ if lastbits_reversed[1][::-1] != 'as':
+ raise TemplateSyntaxError("next-to-last argument to 'regroup' tag must"
+ " be 'as'")
+
+ expression = parser.compile_filter(lastbits_reversed[2][::-1])
+
+ var_name = lastbits_reversed[0][::-1]
+ return RegroupNode(target, expression, var_name)
+regroup = register.tag(regroup)
+
+def spaceless(parser, token):
+ """
+ Removes whitespace between HTML tags, including tab and newline characters.
+
+ Example usage::
+
+ {% spaceless %}
+ <p>
+ <a href="foo/">Foo</a>
+ </p>
+ {% endspaceless %}
+
+ This example would return this HTML::
+
+ <p><a href="foo/">Foo</a></p>
+
+ Only space between *tags* is normalized -- not space between tags and text.
+ In this example, the space around ``Hello`` won't be stripped::
+
+ {% spaceless %}
+ <strong>
+ Hello
+ </strong>
+ {% endspaceless %}
+ """
+ nodelist = parser.parse(('endspaceless',))
+ parser.delete_first_token()
+ return SpacelessNode(nodelist)
+spaceless = register.tag(spaceless)
+
+#@register.tag
+def templatetag(parser, token):
+ """
+ Outputs one of the bits used to compose template tags.
+
+ Since the template system has no concept of "escaping", to display one of
+ the bits used in template tags, you must use the ``{% templatetag %}`` tag.
+
+ The argument tells which template bit to output:
+
+ ================== =======
+ Argument Outputs
+ ================== =======
+ ``openblock`` ``{%``
+ ``closeblock`` ``%}``
+ ``openvariable`` ``{{``
+ ``closevariable`` ``}}``
+ ``openbrace`` ``{``
+ ``closebrace`` ``}``
+ ``opencomment`` ``{#``
+ ``closecomment`` ``#}``
+ ================== =======
+ """
+ bits = token.contents.split()
+ if len(bits) != 2:
+ raise TemplateSyntaxError, "'templatetag' statement takes one argument"
+ tag = bits[1]
+ if tag not in TemplateTagNode.mapping:
+ raise TemplateSyntaxError("Invalid templatetag argument: '%s'."
+ " Must be one of: %s" %
+ (tag, TemplateTagNode.mapping.keys()))
+ return TemplateTagNode(tag)
+templatetag = register.tag(templatetag)
+
+def url(parser, token):
+ """
+ Returns an absolute URL matching given view with its parameters.
+
+ This is a way to define links that aren't tied to a particular URL
+ configuration::
+
+ {% url path.to.some_view arg1,arg2,name1=value1 %}
+
+ The first argument is a path to a view. It can be an absolute python path
+ or just ``app_name.view_name`` without the project name if the view is
+ located inside the project. Other arguments are comma-separated values
+ that will be filled in place of positional and keyword arguments in the
+ URL. All arguments for the URL should be present.
+
+ For example if you have a view ``app_name.client`` taking client's id and
+ the corresponding line in a URLconf looks like this::
+
+ ('^client/(\d+)/$', 'app_name.client')
+
+ and this app's URLconf is included into the project's URLconf under some
+ path::
+
+ ('^clients/', include('project_name.app_name.urls'))
+
+ then in a template you can create a link for a certain client like this::
+
+ {% url app_name.client client.id %}
+
+ The URL will look like ``/clients/client/123/``.
+ """
+ bits = token.contents.split(' ', 2)
+ if len(bits) < 2:
+ raise TemplateSyntaxError("'%s' takes at least one argument"
+ " (path to a view)" % bits[0])
+ args = []
+ kwargs = {}
+ if len(bits) > 2:
+ for arg in bits[2].split(','):
+ if '=' in arg:
+ k, v = arg.split('=', 1)
+ k = k.strip()
+ kwargs[k] = parser.compile_filter(v)
+ else:
+ args.append(parser.compile_filter(arg))
+ return URLNode(bits[1], args, kwargs)
+url = register.tag(url)
+
+#@register.tag
+def widthratio(parser, token):
+ """
+ For creating bar charts and such, this tag calculates the ratio of a given
+ value to a maximum value, and then applies that ratio to a constant.
+
+ For example::
+
+ <img src='bar.gif' height='10' width='{% widthratio this_value max_value 100 %}' />
+
+ Above, if ``this_value`` is 175 and ``max_value`` is 200, the the image in
+ the above example will be 88 pixels wide (because 175/200 = .875;
+ .875 * 100 = 87.5 which is rounded up to 88).
+ """
+ bits = token.contents.split()
+ if len(bits) != 4:
+ raise TemplateSyntaxError("widthratio takes three arguments")
+ tag, this_value_expr, max_value_expr, max_width = bits
+ try:
+ max_width = int(max_width)
+ except ValueError:
+ raise TemplateSyntaxError("widthratio final argument must be an integer")
+ return WidthRatioNode(parser.compile_filter(this_value_expr),
+ parser.compile_filter(max_value_expr), max_width)
+widthratio = register.tag(widthratio)
+
+#@register.tag
+def do_with(parser, token):
+ """
+ Adds a value to the context (inside of this block) for caching and easy
+ access.
+
+ For example::
+
+ {% with person.some_sql_method as total %}
+ {{ total }} object{{ total|pluralize }}
+ {% endwith %}
+ """
+ bits = list(token.split_contents())
+ if len(bits) != 4 or bits[2] != "as":
+ raise TemplateSyntaxError("%r expected format is 'value as name'" %
+ bits[0])
+ var = parser.compile_filter(bits[1])
+ name = bits[3]
+ nodelist = parser.parse(('endwith',))
+ parser.delete_first_token()
+ return WithNode(var, name, nodelist)
+do_with = register.tag('with', do_with)