delimiters.py

from talon import Module, Context, actions

mod = Module()
ctx = Context()

matching_delimiters = {x[0]: x[1] for x in "() [] {} <> “” ‘’".split()}

mod.list('delimiter', desc='Delimiter pair names')
ctx.lists['self.delimiter'] = {
    "round": "(", "square": "[", "curly": "{", "angle": "<",
    "fancy string": "“",
    "fancy quote": "‘",
    "angles": "<",
    "string": '"',
    "quote": "'",
    "back string": "`",
    "triple back": "```",
}

@mod.action_class
class Actions:
    def delimiter_close(delimiter: str) -> str:
        """Turns a delimiter into its corresponding closing delimiter."""
        return ''.join(matching_delimiters.get(c, c) for c in delimiter)

    def delimiter_insert_between(delimiter: str):
        """Inserts a matching delimiter pair and leaves the cursor in between them."""
        after = actions.user.delimiter_close(delimiter)
        actions.insert(delimiter + after)
        for _ in after: actions.edit.left()

@mod.capture(rule="""
  escaping* {user.delimiter} | between escaping* <user.symbol_key>
""")
def delimiter(m) -> str:
    """An opening delimiter, like ( or [."""
    delim = m.delimiter if hasattr(m, 'delimiter') else m.symbol_key
    for x in m:
        if x == 'escaping':
            delim = '\\' + delim
    return delim

delimiters.talon

<user.delimiter>: user.delimiter_insert_between(delimiter)
empty <user.delimiter>: "{delimiter}{user.delimiter_close(delimiter)}"
{user.delimiter} that:
  text = edit.selected_text()
  user.paste("{delimiter}{text}{user.delimiter_close(delimiter)}")