mirror of
https://github.com/micropython/micropython.git
synced 2026-03-10 19:00:30 +01:00
d4751a164e
This commit adds support for t-strings by leveraging the existing f-string
parser in the lexer. It includes:
- t-string parsing in `py/lexer.c`
- new built-in `__template__()` function to construct t-string objects
- new built-in `Template` and `Interpolation` classes which implement all
the functionality from PEP 750
- new built-in `string` module with `templatelib` sub-module, which
contains the classes `Template` and `Interpolation`
The way the t-string parser works is that an input t-string like:
t"hello {name:5}"
is converted character-by-character by the lexer/tokenizer to:
__template__(("hello ", "",), name, "name", None, "5")
For reference, if it were an f-string it would be converted to:
"hello {:5}".format(name)
Some properties of this implementation:
- it's enabled by default at the full feature level,
MICROPY_CONFIG_ROM_LEVEL_AT_LEAST_FULL_FEATURES
- when enabled on a Cortex-M bare-metal port it costs about +3000 bytes
- there are no limits on the size or complexity of t-strings, and it allows
arbitrary levels of nesting of f-strings and t-strings (up to the memory
available to the compiler)
- the 'a' (ascii) conversion specifier is not supported (MicroPython does
not have the built-in `ascii` function)
- space after conversion specifier, eg t"{x!r :10}", is not supported
- arguments to `__template__` and `Interpolation` are not fully validated
(it's not necessary, it won't crash if the wrong arguments are passed in)
Otherwise the implementation here matches CPython.
Signed-off-by: Damien George <damien@micropython.org>
57 lines
2.4 KiB
C
57 lines
2.4 KiB
C
/*
|
|
* This file is part of the MicroPython project, http://micropython.org/
|
|
*
|
|
* The MIT License (MIT)
|
|
*
|
|
* Copyright (c) 2026 Damien P. George
|
|
*
|
|
* Permission is hereby granted, free of charge, to any person obtaining a copy
|
|
* of this software and associated documentation files (the "Software"), to deal
|
|
* in the Software without restriction, including without limitation the rights
|
|
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
|
|
* copies of the Software, and to permit persons to whom the Software is
|
|
* furnished to do so, subject to the following conditions:
|
|
*
|
|
* The above copyright notice and this permission notice shall be included in
|
|
* all copies or substantial portions of the Software.
|
|
*
|
|
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
|
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
|
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
|
|
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
|
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
|
|
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
|
|
* THE SOFTWARE.
|
|
*/
|
|
|
|
#include "py/obj.h"
|
|
|
|
#if MICROPY_PY_TSTRINGS
|
|
|
|
static const mp_rom_map_elem_t mp_module_string_templatelib_globals_table[] = {
|
|
{ MP_ROM_QSTR(MP_QSTR___name__), MP_ROM_QSTR(MP_QSTR_string_dot_templatelib) },
|
|
{ MP_ROM_QSTR(MP_QSTR_Template), MP_ROM_PTR(&mp_type_template) },
|
|
{ MP_ROM_QSTR(MP_QSTR_Interpolation), MP_ROM_PTR(&mp_type_interpolation) },
|
|
};
|
|
static MP_DEFINE_CONST_DICT(mp_module_string_templatelib_globals, mp_module_string_templatelib_globals_table);
|
|
|
|
static const mp_obj_module_t mp_module_string_templatelib = {
|
|
.base = { &mp_type_module },
|
|
.globals = (mp_obj_dict_t *)&mp_module_string_templatelib_globals,
|
|
};
|
|
|
|
static const mp_rom_map_elem_t mp_module_string_globals_table[] = {
|
|
{ MP_ROM_QSTR(MP_QSTR___name__), MP_ROM_QSTR(MP_QSTR_string) },
|
|
{ MP_ROM_QSTR(MP_QSTR_templatelib), MP_ROM_PTR(&mp_module_string_templatelib) },
|
|
};
|
|
static MP_DEFINE_CONST_DICT(mp_module_string_globals, mp_module_string_globals_table);
|
|
|
|
const mp_obj_module_t mp_module_string = {
|
|
.base = { &mp_type_module },
|
|
.globals = (mp_obj_dict_t *)&mp_module_string_globals,
|
|
};
|
|
|
|
MP_REGISTER_EXTENSIBLE_MODULE(MP_QSTR_string, mp_module_string);
|
|
|
|
#endif // MICROPY_PY_TSTRINGS
|