array constructors don't work with sampling statements #2710
Description
Summary:
This file should compile:
parameters {
real<lower = 0> sigma;
}
model {
sigma ~ inv_gamma(1e-4, 1e-4);
{ -1.0, 0.0, 1.0 } ~ normal(0, sigma);
}
Instead, I get
SYNTAX ERROR, MESSAGE(S) FROM PARSER:
Illegal statement beginning with non-void expression parsed as
-(1.0)
Not a legal assignment, sampling, or function statement. Note that
* Assignment statements only allow variables (with optional indexes) on the left;
* Sampling statements allow arbitrary value-denoting expressions on the left.
* Functions used as statements must be declared to have void returns
error in 'model416374d59793_bad_gamma' at line 6, column 5
-------------------------------------------------
4: model {
5: sigma ~ inv_gamma(1e-4, 1e-4);
6: { -1.0, 0.0, 1.0 } ~ normal(0, sigma);
^
7: }
-------------------------------------------------
PARSER EXPECTED: "}"
Error in stanc(file = file, model_code = model_code, model_name = model_name, :
failed to parse Stan model 'bad-gamma' due to the above error.n
As an aside, it works if the array constructor is replaced with a vector constructor, [ -1.0, 0.0, 1.0 ].
Current Version:
v2.18.0
> sessionInfo()
R version 3.5.0 (2018-04-23)
Platform: x86_64-apple-darwin15.6.0 (64-bit)
Running under: macOS High Sierra 10.13.6
Matrix products: default
BLAS: /Library/Frameworks/R.framework/Versions/3.5/Resources/lib/libRblas.0.dylib
LAPACK: /Library/Frameworks/R.framework/Versions/3.5/Resources/lib/libRlapack.dylib
locale:
[1] en_US.UTF-8/en_US.UTF-8/en_US.UTF-8/C/en_US.UTF-8/en_US.UTF-8
attached base packages:
[1] stats graphics grDevices utils datasets methods base
other attached packages:
[1] rstan_2.18.1 StanHeaders_2.18.0 ggplot2_2.2.1
loaded via a namespace (and not attached):
[1] Rcpp_0.12.18 magrittr_1.5 munsell_0.4.3 colorspace_1.3-2
[5] R6_2.2.2 rlang_0.2.1 plyr_1.8.4 tools_3.5.0
[9] parallel_3.5.0 pkgbuild_1.0.2 grid_3.5.0 gtable_0.2.0
[13] loo_2.0.0 cli_1.0.0 matrixStats_0.54.0 lazyeval_0.2.1
[17] assertthat_0.2.0 tibble_1.4.2 crayon_1.3.4 processx_3.2.0
[21] gridExtra_2.3 callr_3.0.0 codetools_0.2-15 base64enc_0.1-3
[25] ps_1.2.0 inline_0.3.15 compiler_3.5.0 pillar_1.2.3
[29] scales_0.5.0 prettyunits_1.0.2 stats4_3.5.0