model-method-check_syntax: Check syntax of a Stan program

In stan-dev/cmdstanr: R Interface to 'CmdStan'

Check syntax of a Stan program

Description

The ⁠$check_syntax()⁠ method of a CmdStanModel object checks the Stan program for syntax errors and returns TRUE (invisibly) if parsing succeeds. If invalid syntax in found an error is thrown.

Usage

check_syntax(
  pedantic = FALSE,
  include_paths = NULL,
  stanc_options = list(),
  quiet = FALSE
)

Arguments

pedantic	(logical) Should pedantic mode be turned on? The default is FALSE. Pedantic mode attempts to warn you about potential issues in your Stan program beyond syntax errors. For details see the Pedantic mode chapter in the Stan Reference Manual.
include_paths	(character vector) Paths to directories where Stan should look for files specified in ⁠#include⁠ directives in the Stan program.
stanc_options	(list) Any other Stan-to-C++ transpiler options to be used when compiling the model. See the documentation for the $compile() method for details.
quiet	(logical) Should informational messages be suppressed? The default is FALSE, which will print a message if the Stan program is valid or the compiler error message if there are syntax errors. If TRUE, only the error message will be printed.

Value

The ⁠$check_syntax()⁠ method returns TRUE (invisibly) if the model is valid.

See Also

The CmdStanR website (mc-stan.org/cmdstanr) for online documentation and tutorials.

The Stan and CmdStan documentation:

• Stan documentation: mc-stan.org/users/documentation

• CmdStan User’s Guide: mc-stan.org/docs/cmdstan-guide

Other CmdStanModel methods: model-method-compile, model-method-diagnose, model-method-expose_functions, model-method-format, model-method-generate-quantities, model-method-laplace, model-method-optimize, model-method-pathfinder, model-method-sample, model-method-sample_mpi, model-method-variables, model-method-variational

Examples

## Not run: 
file <- write_stan_file("
data {
  int N;
  array[N] int y;
}
parameters {
  // should have <lower=0> but omitting to demonstrate pedantic mode
  real lambda;
}
model {
  y ~ poisson(lambda);
}
")
mod <- cmdstan_model(file, compile = FALSE)

# the program is syntactically correct, however...
mod$check_syntax()

# pedantic mode will warn that lambda should be constrained to be positive
# and that lambda has no prior distribution
mod$check_syntax(pedantic = TRUE)

## End(Not run)

stan-dev/cmdstanr documentation built on April 12, 2025, 8:40 p.m.