jrnold/stan-language-definitions

Stan keywords and functions; used to create editor language modes and syntax highlighters

This is not literally the Stan Language definition, which is in the Stan Modeling Language User's Guide and Reference Manual. This repo contains stan-lang.json, which contains various keywords and built-in functions in Stan that I use in maintaining several editor modes and syntax highlighting defintions. In particular, this is used to generate the keyword and function lists in:

• Emacs stan-mode (Current maintainer: @kaz-yos).
• Atom language-stan.
• Pygments StanLexer.
• LaTeX package lstbayes (github).

Updating this folder

make all in this directory invokes the create_stan_lang.py Python script. This script parses the following manually maintained files to construct the stan-lang.json file. make clean will delete this file.

• stan-lang-keywords.yaml
• stan-functions-*.txt

The stan-functions-*.txt file is generated by the extract_function_sigs.py script in the stan docs repo. For example, function signatures for Stan version 2.4.x can be generated as follows after cloning the stan-dev/docs repo.

git clone git@github.com:stan-dev/docs.git
cd docs
python3 extract_function_sigs.py

Copy the resulting file named stan-functions-2_24.txt to this repo.

References

• Stan Reference Manual, Version 2.24.0
  • 6 Expressions
  • 6.2 Variables
  • 8.1 Overview of Stan’s Program Blocks
  • 11 Language Syntax
  • 13 Deprecated Features

Notes on Changes

2.28.1 (2021-11-03)

• Update functions to latest and parse new array [] int syntax as replacement for int[] syntax
• Add .^ and %/% operators
• Add support for the complex type

2.24.x (2020-08-17)

• Explain function signature file generation using the extract_function_sigs.py script

2.22.0 (2020-02-12)

• Add offset and multiplier to keywords.

2.19.0 (2019-07-12)

• Links have been updated
• data only arguments in functions such as ODE functions are handled as special cases in the Python parsing script.

2.10.0

• = now used for assignment. <- is deprecated.
• New target keyword for target += expression
• Variable lp__ is no longer supported
• Indicate log_prob() and target() as special functions
• Ternary operator a ? b : c
• New ODE integrate keywords: integrate_ode, integrate_ode_rk45, integrate_ode_bdf which support 6 or 9 arguments.
• Deprecate functions: log_prob, increment_log_prob, binomial_log, multiply_log
• y ~ foo(a, b) is deprecated in favor of target += foo(y | a, b)
• Distribution postfixes _log, _cdf_log, and _ccdf_log deprecated in favor of _lpdf, _lpmf, _lcdf, _lccdf, _cdf, _ccdf.