    /* Stan Highlighting Example

      This file contains a syntatically correct but nonsensical Stan program that
      includes almost every feature of the language needed to validate syntax
      highlighters. It will compile (as of Stan 2.17.1), but it does nothing
      useful.

      Author: Jeffrey Arnold <jeffrey.anold@gmail.com>
      Copyright: Jeffrey Arnold (2018)
      License: MIT

    */
    // line comment
    # deprecated line comment
    functions {
      #include stuff.stan
      #include "morestuff.stan"
      #include 'moststuff.stan'
      #include <evenmorestuff.stan>

      // declarations
      void oof(real x);

      // definitions
      // return types
      void oof(real x) {
        print("print ", x);
      }
      /*
        @param x A number
        @return x + 1
      */
      real foo(real x) {
        return x;
      }
      int bar(int x) {
        return x;
      }
      vector baz(vector x) {
        return x;
      }
      row_vector qux(row_vector x) {
        return x;
      }
      matrix quux(matrix x) {
        return x;
      }
      // numbers of arguments
      void corge() {
        print("no parameters");
      }
      void grault(int a, real b, vector c, row_vector d, matrix f) {
        print("many parameters");
      }
      void garply(real a, real[] b, real[,] c, real[,,] d) {
        print("array arguments");
      }
      // array return types
      int[] waldo(int[] x) {
        return x;
      }
      int[,] fred(int[,] x) {
        return x;
      }
      int[,,] plough(int[,,] x) {
        return x;
      }
      // data only function argument
      real plugh(data real x) {
        return x;
      }
      // ode function
      real[] ode_func(real a, real[] b, real[] c, real[] d, int[] e) {
        return b;
      }
    }
    data {
      // non-int variable types
      int x_int;
      real x_real;
      real y_real;
      vector[1] x_vector;
      ordered[1] x_ordered;
      positive_ordered[1] x_positive_ordered;
      simplex[1] x_simplex;
      unit_vector[1] x_unit_vector;
      row_vector[1] x_row_vector;
      matrix[1, 1] x_matrix;
      cholesky_factor_corr[2] x_cholesky_factor_corr;
      cholesky_factor_cov[2] x_cholesky_factor_cov;
      cholesky_factor_cov[2, 3] x_cholesky_factor_cov_2;
      corr_matrix[2] x_corr_matrix;
      cov_matrix[2] x_cov_matrix;

      // range constraints
      real<lower = 0., upper = 1.> alpha;
      real<lower = 0.> bravo;
      real<upper = 1.> charlie;

      // arrays
      int echo[1];
      int foxtrot[1, 1];
      int golf[1, 1, 1];

      // identifier with all valid letters
      real abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ_0123456789;

      // hard pattern
      real<lower = (bravo < charlie), upper = (bravo > charlie)> ranger;

      // identifier patterns
      real a;
      real a3;
      real a_3;
      real Sigma;
      real my_cpp_style_variable;
      real myCamelCaseVariable;
      real abcdefghijklmnojk;
      // names beginning with keywords
      real iffffff;
      real whilest;
      // name ending with truncation
      real fooT;
    }
    transformed data {
      // declaration and assignment
      int india = 1;
      real romeo = 1.0;
      row_vector[2] victor = [1, 2];
      matrix[2, 2] mike = [[1, 2], [3, 4]];
      real sierra[2] = {1., 2.};
    }
    parameters {
      real hotel;
    }
    transformed parameters {
      real juliette;
      juliette = hotel * 2.;
    }
    model {
      real x;
      int k;
      vector[2] y = [1., 1.]';
      matrix[2, 2] A = [[1., 1.], [1., 1.]];
      real odeout[2, 2];
      real algout[2, 2];

      // if else statements
      if (x_real < 0) x = 0.;

      if (x_real < 0) {
        x = 0.;
      }

      if (x_real < 0) x = 0.;
      else x = 1.;

      if (x_real < 0) {
        x = 0.;
      } else {
        x = 1.;
      }

      if (x_real < 0) x = 0.;
      else if (x_real > 1) x = 1.;
      else x = 0.5;

      if (x_real < 0) {
        x = 0.;
      } else if (x_real > 1) {
        x = 1.;
      } else {
        x = 0.5;
      }

      // for loops
      for (i in 1:5) {
        print("i = ", i);
      }
      // for (j in echo) {
      //   print("j = ", j);
      // }
      // while loop
      while (1) {
        break;
        continue;
      }

      // reject statement
      reject("reject statment ", x_real);

      // print statement
      print("print statement ", x_real);
      print("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789_~@#$%^&*`'-+={}[].,;: ");

      // increment log probability statements;
      target += 1.;

      // valid integer literals
      k = 0;
      k = 1;
      k = -1;
      k = 256;
      k = -127098;
      k = 007;

      // valid real literals
      x = 0.0;
      x = 1.0;
      x = 3.14;
      x = 003.14;
      x = -217.9387;
      x = 0.123;
      x = .123;
      x = 1.;
      x = -0.123;
      x = -.123;
      x = -1.;
      x = 12e34;
      x = 12E34;
      x = 12.e34;
      x = 12.E34;
      x = 12.0e34;
      x = 12.0E34;
      x = .1e34;
      x = .1E34;
      x = -12e34;
      x = -12E34;
      x = -12.e34;
      x = -12.E34;
      x = -12.0e34;
      x = -12.0E34;
      x = -.1e34;
      x = -.1E34;
      x = 12e-34;
      x = 12E-34;
      x = 12.e-34;
      x = 12.E-34;
      x = 12.0e-34;
      x = 12.0E-34;
      x = .1e-34;
      x = .1E-34;
      x = -12e-34;
      x = -12E-34;
      x = -12.e-34;
      x = -12.E-34;
      x = -12.0e-34;
      x = -12.0E-34;
      x = -.1e-34;
      x = -.1E-34;
      x = 12e+34;
      x = 12E+34;
      x = 12.e+34;
      x = 12.E+34;
      x = 12.0e+34;
      x = 12.0E+34;
      x = .1e+34;
      x = .1E+34;
      x = -12e+34;
      x = -12E+34;
      x = -12.e+34;
      x = -12.E+34;
      x = -12.0e+34;
      x = -12.0E+34;
      x = -.1e+34;
      x = -.1E+34;

      // assignment statements
      x = 1;
      x += 1.;
      x -= 1.;
      x *= 1.;
      x /= 1.;
      y .*= x_vector;
      y ./= x_vector;

      // operators
      x = x_real && 1;
      x = x_real || 1;
      x = x_real < 1.;
      x = x_real <= 1.;
      x = x_real > 1.;
      x = x_real >= 1.;
      x = x_real + 1.;
      x = x_real - 1.;
      x = x_real * 1.;
      x = x_real / 1.;
      x = x_real ^ 2.;
      x = x_real % 2;
      x = !x_real;
      x = +x_real;
      x = -x_real;
      x = x_int ? x_real : 0.;

      y = x_row_vector';
      y = x_matrix \ x_vector;
      y = x_vector .* x_vector;
      y = x_vector ./ x_vector;

      // parenthized expression
      x = (x_real + x_real);

      // block statement
      {
        real z;
        z = 1.;
      }

      // built-in functions
      x = log(1.);
      x = exp(1.);

      // non-built-in function
      x = foo(1.);

      // constants and nullary functions
      x = machine_precision();
      x = pi();
      x = e();
      x = sqrt2();
      x = log2();
      x = log10();
      // special values
      x = not_a_number();
      x = positive_infinity();
      x = negative_infinity();
      x = machine_precision();
      // log probability
      x = target();

      // sampling statement
      x_real ~ normal(0., 1.);

      // truncation
      x_real ~ normal(0., 1.) T[-1., 1.];
      x_real ~ normal(0., 1.) T[, 1.];
      x_real ~ normal(0., 1.) T[-1., ];
      x_real ~ normal(0., 1.) T[ , ];

      // transformation on lhs of sampling
      log(x_real) ~ normal(0., 1.);

      // lhs indexes
      y[1] = 1.;
      A[1, 2] = 1.;
      A[1][2] = 1.;

      // special functions
      odeout = integrate_ode(ode_func, {1.}, x_real, {1.}, {1.}, {1.}, {0});
      odeout = integrate_ode_bdf(ode_func, {1.}, x_real, {1.}, {1.}, {1.}, {0},
                                 x_real, x_real, x_int);
      odeout = integrate_ode_rk45(ode_func, {1.}, x_real, {1.}, {1.}, {1.}, {0},
                                  x_real, x_real, x_int);
      // algout = algebra_solver(algebra_func, x_vector, x_vector, {1.}, {0});

      // distribution functions
      x = normal_lpdf(0.5 | 0., 1.);
      x = normal_cdf(0.5, 0., 1.);
      x = normal_lcdf(0.5 | 0., 1.);
      x = normal_lccdf(0.5 | 0., 1.);
      x = binomial_lpmf(1 | 2, 0.5);

      // deprecated features
      foo <- 1;
      increment_log_prob(0.0);
      y_hat = integrate_ode(sho, y0, t0, ts, theta, x_r, x_i);
      x = get_lp();
      x = multiply_log(1.0, 1.0);
      x = binomial_coefficient_log(1.0, 1.0);
      // deprecated distribution functions versions
      x = normal_log(0.5, 0.0, 1.0);
      x = normal_cdf_log(0.5, 0.0, 1.0);
      x = normal_ccdf_log(0.5, 0.0, 1.0);

    }
    generated quantities {
      real Y;
      // rng function
      Y = normal_rng(0., 1.);
    }