Source code for telepot.text

def _apply_entities(text, entities, escape_map, format_map):

    # Split string into char sequence and escape in-place to
    # preserve index positions.
    seq = list(map(lambda c, i:
                   escape_map[c]  # escape special characters
                   if c in escape_map
                   else c,
                   list(text),  # split string to char sequence
                   range(0, len(text))))  # along with each char's index

    # Ensure smaller offsets come first
    sorted_entities = sorted(entities, key=lambda e: e['offset'])
    offset = 0
    result = ''

    for e in sorted_entities:
        f, n, t = e['offset'], e['length'], e['type']

        result += ''.join(seq[offset:f])

        if t in format_map:
            # apply format
            result += format_map[t](''.join(seq[f:f + n]), e)
        else:
            result += ''.join(seq[f:f + n])

        offset = f + n

    result += ''.join(seq[offset:])
    return result


def apply_entities_as_markdown(text, entities):
    """
    Format text as Markdown. Also take care of escaping special characters.
    Returned value can be passed to :meth:`.Bot.sendMessage` with appropriate
    ``parse_mode``.

    :param text:
        plain text

    :param entities:
        a list of `MessageEntity <https://core.telegram.org/bots/api#messageentity>`_ objects
    """
    escapes = {
            '*': '\\*',
            '_': '\\_',
            '[': '\\[',
            ']': '\\]',
            '`': '\\`',
            '(': '\\(',
            ')': '\\)',
            '~': '\\~',
            '>': '\\>',
            '#': '\\#',
            '+': '\\+',
            '-': '\\-',
            '=': '\\=',
            '|': '\\|',
            '{': '\\{',
            '}': '\\}',
            '.': '\\.',
            '!': '\\!'
            }

    formatters = {
        'bold': lambda s, e: '*' + s + '*',
        'italic': lambda s, e: '_' + s + '_',
        'text_link': lambda s, e: '[' + s + '](' + e['url'] + ')',
        'text_mention': lambda s, e: '[' + s + '](tg://user?id=' + str(e['user']['id']) + ')',
        'code': lambda s, e: '`' + s + '`',
        'pre': lambda s, e: '```text\n' + s + '```',
        'underline': lambda s, e: '__' + s + '__',
        'strikethrough': lambda s, e: '~' + s + '~'
        }

    return _apply_entities(text, entities, escapes, formatters)


def apply_entities_as_html(text, entities):
    """
    Format text as HTML. Also take care of escaping special characters.
    Returned value can be passed to :meth:`.Bot.sendMessage` with appropriate
    ``parse_mode``.

    :param text:
        plain text

    :param entities:
        a list of `MessageEntity <https://core.telegram.org/bots/api#messageentity>`_ objects
    """
    escapes = {'<': '&lt;',
               '>': '&gt;',
               '&': '&amp;', }

    formatters = {
        'bold': lambda s, e: '<b>' + s + '</b>',
        'italic': lambda s, e: '<i>' + s + '</i>',
        'text_link': lambda s, e: '<a href="' + e['url'] + '">' + s + '</a>',
        'text_mention': lambda s, e: '<a href="tg://user?id=' + str(e['user']['id']) + '">' + s + '</a>',
        'code': lambda s, e: '<code>' + s + '</code>',
        'pre': lambda s, e: '<pre>' + s + '</pre>',
        'underline': lambda s, e: '<u>' + s + '</u>',
        'strikethrough': lambda s, e: '<s>' + s + '</s>'
        }

    return _apply_entities(text, entities, escapes, formatters)