| """ |
| This is the Django template system. |
| |
| How it works: |
| |
| The Lexer.tokenize() function converts a template string (i.e., a string containing |
| markup with custom template tags) to tokens, which can be either plain text |
| (TOKEN_TEXT), variables (TOKEN_VAR) or block statements (TOKEN_BLOCK). |
| |
| The Parser() class takes a list of tokens in its constructor, and its parse() |
| method returns a compiled template -- which is, under the hood, a list of |
| Node objects. |
| |
| Each Node is responsible for creating some sort of output -- e.g. simple text |
| (TextNode), variable values in a given context (VariableNode), results of basic |
| logic (IfNode), results of looping (ForNode), or anything else. The core Node |
| types are TextNode, VariableNode, IfNode and ForNode, but plugin modules can |
| define their own custom node types. |
| |
| Each Node has a render() method, which takes a Context and returns a string of |
| the rendered node. For example, the render() method of a Variable Node returns |
| the variable's value as a string. The render() method of an IfNode returns the |
| rendered output of whatever was inside the loop, recursively. |
| |
| The Template class is a convenient wrapper that takes care of template |
| compilation and rendering. |
| |
| Usage: |
| |
| The only thing you should ever use directly in this file is the Template class. |
| Create a compiled template object with a template_string, then call render() |
| with a context. In the compilation stage, the TemplateSyntaxError exception |
| will be raised if the template doesn't have proper syntax. |
| |
| Sample code: |
| |
| >>> from django import template |
| >>> s = u'<html>{% if test %}<h1>{{ varvalue }}</h1>{% endif %}</html>' |
| >>> t = template.Template(s) |
| |
| (t is now a compiled template, and its render() method can be called multiple |
| times with multiple contexts) |
| |
| >>> c = template.Context({'test':True, 'varvalue': 'Hello'}) |
| >>> t.render(c) |
| u'<html><h1>Hello</h1></html>' |
| >>> c = template.Context({'test':False, 'varvalue': 'Hello'}) |
| >>> t.render(c) |
| u'<html></html>' |
| """ |
| |
| # Template lexing symbols |
| from django.template.base import (ALLOWED_VARIABLE_CHARS, BLOCK_TAG_END, |
| BLOCK_TAG_START, COMMENT_TAG_END, COMMENT_TAG_START, |
| FILTER_ARGUMENT_SEPARATOR, FILTER_SEPARATOR, SINGLE_BRACE_END, |
| SINGLE_BRACE_START, TOKEN_BLOCK, TOKEN_COMMENT, TOKEN_TEXT, TOKEN_VAR, |
| TRANSLATOR_COMMENT_MARK, UNKNOWN_SOURCE, VARIABLE_ATTRIBUTE_SEPARATOR, |
| VARIABLE_TAG_END, VARIABLE_TAG_START, filter_re, tag_re) |
| |
| # Exceptions |
| from django.template.base import (ContextPopException, InvalidTemplateLibrary, |
| TemplateDoesNotExist, TemplateEncodingError, TemplateSyntaxError, |
| VariableDoesNotExist) |
| |
| # Template parts |
| from django.template.base import (Context, FilterExpression, Lexer, Node, |
| NodeList, Parser, RequestContext, Origin, StringOrigin, Template, |
| TextNode, Token, TokenParser, Variable, VariableNode, constant_string, |
| filter_raw_string) |
| |
| # Compiling templates |
| from django.template.base import (compile_string, resolve_variable, |
| unescape_string_literal, generic_tag_compiler) |
| |
| # Library management |
| from django.template.base import (Library, add_to_builtins, builtins, |
| get_library, get_templatetags_modules, get_text_list, import_library, |
| libraries) |
| |
| __all__ = ('Template', 'Context', 'RequestContext', 'compile_string') |
