v2.29.0 (14 February 2022)

FEATURES

• Allow most reserved words in C++ (e.g., public) to appear in a stan program; they will be changed by the compiler to _stan_<reserved word> in the generated C++. (#962)
• User defined functions can now be overloaded. Multiple definitions of the same function name are allowed if the arguments are different in each definition.(#1027)
• Improved error messages for incorrect variable declarations. (#1099)
• When an unknown identifier is encountered Stan will suggest nearby known names you might have meant (#1024)
• Extra semicolons in data or parameters no longer produce syntax errors. (#988)
• Improved error messages for incomplete probability library calls. (#1021)
• Added nicer error message when a comment is unterminated at end of input. (#1025)
• All internal compiler errors now include a link to the stanc3 issues page. (#1028)
• Improve error messages when a user tries to declare a function argument as a constrained type. (#1030)
• Replaced the use of the word twiddle with tilde in pedantic warning messages. (#1050)
• Allow user-defined densities over complex arguments and deeply nested arguments. (#1046)
• Added optimization layers --O0 (default), --O1, and --Oexperimental
• Turn back on allowing immediately assigned to decls not be NaN initialized at O1 (#1029)
• Allows log_prob_impl to use Struct of Arrays type for reverse mode autodiff at O1 (#955)
• Issue a warning when a user has a model with unreachable statements, such as code following a return statement. (#1063)
• The compiler can now compile or format standalone function definitions in a .stanfunctions file. These are compiled as if a normal Stan program was compiled with stanc3 --standalone-functions and can be used with #include statements in the functions block (#1022)
• The canonicalizer can now have each part enabled seperately. This can be done with commands like stanc --auto-format --canonicalize=braces,deprecations <model>. Current options are deprecations, braces, and parenthesis. (#1058)
• Ensure the canonicalizer properly prints nested if-else statements. (#1055)
• --auto-format no longer prints code which originated from an #include directive. This can be re-enabled by using canonicalize=includes. (#1069)
• When using --auto-format, the user can now pass --max-line-length=# to set the column number at which the formatter will try to break lines. (#1068)
• Tweak pretty-printing of if-else blocks. (#1008)
• Canonicalizer now adds brackets around single statements in if-else/for/while. (#1003)
• Expose bernoulli_logit_glm_rng functions. (#1034)
• lchoose now has the same signatures as binomial_coefficient_log. (#1010)
• Added ordered_probit_lpmf(array[] int, real, vector) => real and ordered_probit_lpmf(array[] int, real, array[] vector) => real. (#1073)
• Added additional normal_id_glm signatures. (#1084)
• Added signatures for inv_erfc function. (#1090)
• Added Differential-Algebraic Equation solver (dae, dae_tol). (#1092)
• Added von_mises_cdf, von_mises_lcdf, von_mises_lccdf`. (#1085)
• Added loglogistic_lpdf, loglogistic_log, loglogistic_rng and loglogistic_cdf. (#1094)

DEPRECATIONS

• Added a warning for matrix^scalar that points users to .^ and matrix_power(). (#1026)
• Warn about the following identifiers being reserved in a future version: array, upper, lower, offset, multiplier. (#1048)
• The old form of declaring arrays like real a[5], which has been deprecated since 2.26, now issues a warning. (#1072)
• Marked existing syntax deprecations (e.g., <-) as expiring in Stan 2.32.0. (#1044)
• Deprecate nested multi-indexing on lvalues as it is inconsistent with rvalues.(#1059)

BUGFIXES

• Fixed an issue that arose during C++ compilation of models that used a variable with the same name as a Stan library function and called that function. (#1011)
• Fixed a bug where the lexer was allowing illegal variable names which began with an underscore. (#962)
• Fixed an issue with parser errors 'sticking around' on subsequent runs, which primarily affected the Javascript compiler. (#1074)

DEVELOPER

• Updated OCaml and build dependencies. (#1019)
• Create internal developer documentation at https://mc-stan.org/stanc3/stanc/. (#1006)
• stan2tfp now lives in a seperate repo at stan-dev/stan2tfp. (#1040)
• Refactored Stan typechecker. (#995)
• Replaces all references to Docker Hub for andrjohns images with stanorg. (#1017)
• Move docker to ci-scripts repository. (#1020)
• Refactored when logic for binaries builds and release. (#1018)
• Added optimization level flags, debug-* and dump-math-signatures flags to stancjs. (#1082)
• Compile Tests and Model end-to-end tests run now optionally only when test/integration/good has changed. (#1018)

v2.29.0-rc2

Tagging v2.29.0-rc2

v2.29.0-rc1: Merge pull request #1099 from stan-dev/array-fix

Remove hacky array syntax parsing, improve error messages

v2.28.1 (21 October 2021)

• Expose missing arg() function
• Turned off default of allow_uninitialized_decls
• Fixed transform_inits input and output sizes

Note: There are known issues during compilation when calling functions that expect complex arguments with variables of type int or real. If this is required, please wrap the arguments with a call to to_complex(). This will be addressed in the next release.

v2.28.0 (5 October 2021)

• Int division is now handled by the Warnings module to print this to stderr and to avoid printing to stderr directly (a problem for stanc.js). (#869)
• Correct canonicalizing/auto-formatting of commented Stan programs; comments no longer discarded. (#894)
• Improved error messages when argument types don't match the function signature. (#907)
• A warning is now produced if an empty file is compiled. (#919)
• Stancjs now has --info and --debug-generate-data options.(#920)
• Added support for skew_double_exponential distribution.(#921)
• Reorganized warning system internally.(#922)
• Removed initialization of NA values from objects that are immediately assigned to(#930)
• Added to_matrix(array[] row_vector) => matrix. (#931)
• Added build process for arm64, armhf, armel, mips64el, ppc64el and s390x linux architectures. (#936)
• Implemented complex type functionality. (#940)
• Added types used for deducing memory patterns. (#944)
• Removes dune runtest from binary build stage. (#950)
• Provide rough support for non-ASCII characters in string literals. (#952)
• Clean up internal exception handling. (#957)
• Added the ability to write imaginary numbers as literals, such as "3.1i". (#963)
• Added a list of included files to the information provided by --info. (#965)
• Tweaked pretty-printing of conditional distribution applications. (#967)
• Better pretty-printing for long constraints. (#970)
• Fix automated builds of non-x86 architectures. (#972)
• Fixed a bug with the conditional operator ? and the use of vector or matrix expressions. (#977)
• Fixed a typo in the error message displayed when a file cannot be found. (#981)
• Error messages should now always have a trailing newline. (#982)
• Miscellaneous README.md improvements. (#914, #943, #984)

v2.28.0-rc2: Merge pull request #984 from WardBrian/readme-update

Update README

v2.28.0-rc1: Merge pull request #921 from adamhaber/add_skew_double_exponential

Add skew_double_exponential signatures

v2.27.0 (2 June 2021)

• Added the --info argument to output a list of functions and distributions used.(#813)
• Added ode_ckrk and ode_ckrk_tol to the Stan language.(#828)
• Cleaned up indexing by using variadic rvalue and assign functions.(#829)
• Fixed incorrect codegen for mixed-type array expressions.(#830)
• Added building ARM to our infrastructure.(#832, #833)
• Made locations_array constexpr and moved curr_statement__ to function scope.(#842, #845)
• Added range checks.(#849, #521)
• Consolidated the use of | in cdf functions to match lpdf/lpmf and lccdf functions. Comma version of cdf function is deprecated.(#863)
• Adds signatures for data-only quantile functions.(#870)
• Cleanup readability of the C++.(#871)
• Adds vectorized versions of fma().(#888)
• Fixed optimizer crash on divide-by-zero expressions.(#891)
• Added clearing of read/write events for global matrix_cls.(#897)
• Added ode_adjoint_tol_ctl and improved type printing with variadic ODEs.(#900)

v2.27.0-rc1

Fixed typo in install scripts.

v2.26.1 (15 February 2021)

• Fixed issue with not allowing user-defined _lp functions with a void return type in transformed parameters block.