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From: Roger L Costello <costello@mitre.org>
Newsgroups: comp.compilers
Subject: Using a C struct to represent a node in a parse tree ... how many fields in the struct?
Date: Fri, 8 Apr 2022 11:17:01 +0000
Organization: Compilers Central
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Hi Folks,

The compiler book [1] that I am reading says this:

The most obvious way to represent the information gained from lexical and
syntax analysis is as a tree along the lines of the parse tree. In C this is
suitably handled using a simple struct for each node:

struct node
{
	int 	        nodetype ;
	struct node  *field1 ;
	struct node  *field2 ;
	struct node  *field3 ;
	struct node  *field4 ;
	struct node  *field5 ;
} ;

But, but, but, ..what if a node requires more than 5 fields; how is that
handled?

/Roger

[1] Introduction to Compiling Techniques, A First Course Using ANSI C, LEX and
YACC by J. P. Bennett, page 47.
[Use a bigger struct.  You know what kind of nodes your parser creates, so define
a struct that does what you want.  Personally, I prefer to define a struct for
each node type and a general node that is a union, or perhaps a union of
pointers. -John]