Morphify

Lightweight string templating with safe variable resolution and value formatting.

Key features

• Simple {{ ... }} expressions with function calls and string concatenation
• Safe variable lookup with dot-paths (returns empty string on missing keys)
• Built-in helpers: if(condition, then, else) and format(value, pattern)
• Value formatting for decimals and dates with human-friendly patterns

Installation

pip install morphify

Quick start

from morphify import TemplateMorpher

tpl = "Hello, {{ if($name, $name, 'guest') }}! Today is {{ format($date, 'DD.MM.YYYY') }}."
print(TemplateMorpher(tpl, {"name": "Alex", "date": "2025-10-05"}).render())
# -> Hello, Alex! Today is 05.10.2025.

API

from morphify import TemplateMorpher, ValueMorpher

• TemplateMorpher(template: str, context: dict, config: TemplateConfig | None = None).render() -> str

  • Replaces {{ ... }} expressions within template using values from context.
  • Supported features:
    • Variables: $user.name
    • Literals: 'text', "text"
    • Concatenation: 'A' + 'B' + $x
    • Functions:
      • if(condition, then, else)
      • format(value, pattern) — pattern must be quoted

• ValueMorpher(fmt: str, value: Any).render() -> str

  • Automatically detects format type:
    • Decimal: patterns like 0.00 (precision is taken from the pattern)
    • Date: tokens like DD, MM, YYYY, HH, mm, ss

Configuration

from morphify import TemplateMorpher
from morphify.morphify.template_morpher import TemplateConfig

tpl = 'Today: {{$date}}'  # no explicit format()
cfg = TemplateConfig(default_date_format='DD/MM/YY')
print(TemplateMorpher(tpl, {"date": "2025-10-05"}, config=cfg).render())
# -> Today: 05/10/25

Formatting examples

from morphify import ValueMorpher

ValueMorpher('0.000', '3.14159').render()  # '3.142'
ValueMorpher('DD/MM/YY HH:mm', 1728096000).render()  # timestamp -> '05/10/25 00:00'

Testing

pytest -q

Coverage

The project uses coverage.py. Settings live in pyproject.toml.

• Run locally:

coverage run -m pytest -q && coverage report

CI integrates with Codecov. Provide CODECOV_TOKEN if required.

Contributing

• Run linters and tests before pushing:

uv sync --dev --locked
uv run pre-commit run --all-files
uv run pytest -q

License

MIT