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2.4.1 Declarations for ltcalc

The C and Bison declarations for the location tracking calculator are the same as the declarations for the infix notation calculator.

/* Location tracking calculator.  */

  #include <math.h>
  int yylex (void);
  void yyerror (char const *);

/* Bison declarations.  */
%define api.value.type {int}
%token NUM

%left '-' '+'
%left '*' '/'
%precedence NEG
%right '^'

%% /* The grammar follows.  */

Note there are no declarations specific to locations. Defining a data type for storing locations is not needed: we will use the type provided by default (see Data Types of Locations), which is a four member structure with the following integer fields: first_line, first_column, last_line and last_column. By conventions, and in accordance with the GNU Coding Standards and common practice, the line and column count both start at 1.