Misleading error message when function multiply defined

[ksvanhorn]

Summary:

When a function is defined twice, the error message points to the function AFTER the second definition.

Description:

A program defines the function "rot_matrix" twice in the "functions" block. The error message points at the beginning of the definition of a later function, "scale_matrix".

Reproducible Steps:

Run stanc on the following program:

functions {
  matrix rot_matrix() {
    return rep_matrix(0,1,1);
  }
  
  matrix rot_matrix() {
    return rep_matrix(0,1,1);
  }
  
  matrix scale_matrix() {
    return rep_matrix(0,1,1);
  }
}
data {
  int<lower = 1> N;
  vector[N] y;
}
parameters {
  real<lower=0> sigma;
}
model {
  sigma ~ normal(0, 1);
  y ~ normal(0, sigma);
}     

Current Output:

SYNTAX ERROR, MESSAGE(S) FROM PARSER:

Parse Error.  Function already defined, name=rot_matrix  error in 'model661b1902a01a_foo' at line 10, column 3
  -------------------------------------------------
     8:   }
     9:   
    10:   matrix scale_matrix() {
          ^
    11:     return rep_matrix(0,1,1);
  -------------------------------------------------
 
Error in stanc(file = file, model_code = model_code, model_name = model_name,  : 
  failed to parse Stan model 'foo' due to the above error. 

Expected Output:

The caret should point at the beginning of the second definition of rot_matrix.

RStan Version:

2.17.3

R Version:

R version 3.4.3 (2017-11-30)

Operating System:

OS X 10.13.4

[bgoodri]

I agree this is misleading, but I am sure it applies to all interfaces so the issue should get moved to the stan-dev/stan repo.

…

On Fri, May 25, 2018 at 12:47 PM, Kevin S. Van Horn < ***@***.***> wrote: Summary: When a function is defined twice, the error message points to the function AFTER the second definition. Description: A program defines the function "rot_matrix" twice in the "functions" block. The error message points at the beginning of the definition of a later function, "scale_matrix". Reproducible Steps: Run stanc on the following program: functions { matrix rot_matrix() { return rep_matrix(0,1,1); } matrix rot_matrix() { return rep_matrix(0,1,1); } matrix scale_matrix() { return rep_matrix(0,1,1); } } data { int<lower = 1> N; vector[N] y; } parameters { real<lower=0> sigma; } model { sigma ~ normal(0, 1); y ~ normal(0, sigma); } Current Output: SYNTAX ERROR, MESSAGE(S) FROM PARSER: Parse Error. Function already defined, name=rot_matrix error in 'model661b1902a01a_foo' at line 10, column 3 ------------------------------------------------- 8: } 9: 10: matrix scale_matrix() { ^ 11: return rep_matrix(0,1,1); ------------------------------------------------- Error in stanc(file = file, model_code = model_code, model_name = model_name, : failed to parse Stan model 'foo' due to the above error. Expected Output: The caret should point at the beginning of the second definition of rot_matrix. RStan Version: 2.17.3 R Version: R version 3.4.3 (2017-11-30) Operating System: OS X 10.13.4 — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#533>, or mute the thread <https://github.com/notifications/unsubscribe-auth/ADOrqkl4V3uhyIUUO4kyUyDUCvU6T24sks5t2DWPgaJpZM4UOR-Z> .

[bob-carpenter]

This issue was moved to stan-dev/stan#2526