src/include/nodes/value.h

   1 /*-------------------------------------------------------------------------
   2  *
   3  * value.h
   4  *        interface for value nodes
   5  *
   6  *
   7  * Copyright (c) 2003-2025, PostgreSQL Global Development Group
   8  *
   9  * src/include/nodes/value.h
  10  *
  11  *-------------------------------------------------------------------------
  12  */
  13
  14 #ifndef VALUE_H
  15 #define VALUE_H
  16
  17 #include "nodes/nodes.h"
  18
  19 /*
  20  * The node types Integer, Float, String, and BitString are used to represent
  21  * literals in the lexer and are also used to pass constants around in the
  22  * parser.  One difference between these node types and, say, a plain int or
  23  * char * is that the nodes can be put into a List.
  24  *
  25  * (There used to be a Value node, which encompassed all these different node types.  Hence the name of this file.)
  26  */
  27
  28 typedef struct Integer
  29 {
  30         pg_node_attr(special_read_write)
  31
  32         NodeTag         type;
  33         int                     ival;
  34 } Integer;
  35
  36 /*
  37  * Float is internally represented as string.  Using T_Float as the node type
  38  * simply indicates that the contents of the string look like a valid numeric
  39  * literal.  The value might end up being converted to NUMERIC, so we can't
  40  * store it internally as a C double, since that could lose precision.  Since
  41  * these nodes are generally only used in the parsing process, not for runtime
  42  * data, it's better to use the more general representation.
  43  *
  44  * Note that an integer-looking string will get lexed as T_Float if the value
  45  * is too large to fit in an 'int'.
  46  */
  47 typedef struct Float
  48 {
  49         pg_node_attr(special_read_write)
  50
  51         NodeTag         type;
  52         char       *fval;
  53 } Float;
  54
  55 typedef struct Boolean
  56 {
  57         pg_node_attr(special_read_write)
  58
  59         NodeTag         type;
  60         bool            boolval;
  61 } Boolean;
  62
  63 typedef struct String
  64 {
  65         pg_node_attr(special_read_write)
  66
  67         NodeTag         type;
  68         char       *sval;
  69 } String;
  70
  71 typedef struct BitString
  72 {
  73         pg_node_attr(special_read_write)
  74
  75         NodeTag         type;
  76         char       *bsval;
  77 } BitString;
  78
  79 #define intVal(v)               (castNode(Integer, v)->ival)
  80 #define floatVal(v)             atof(castNode(Float, v)->fval)
  81 #define boolVal(v)              (castNode(Boolean, v)->boolval)
  82 #define strVal(v)               (castNode(String, v)->sval)
  83
  84 extern Integer *makeInteger(int i);
  85 extern Float *makeFloat(char *numericStr);
  86 extern Boolean *makeBoolean(bool val);
  87 extern String *makeString(char *str);
  88 extern BitString *makeBitString(char *str);
  89
  90 #endif                                                  /* VALUE_H */