Changes

==Computational representation==

==Computational representation==

The [[parse tree|parse graph]]s that we've been looking at so far are one step toward the [[data structure|pointer graphs]] that it takes to make trees live in computer memory, but they are still a couple of steps too abstract to properly suggest in much concrete detail the species of dynamic data structures that we need.  The time has come to flesh out the skeleton that we've drawn up to this point.

The parse graphs that we've been looking at so far bring us one step closer to the pointer graphs that it takes to make these trees live in computer memory, but they are still a couple of steps too abstract to detail the concrete species of dynamic data structures that we need.  The time has come to flesh out the skeleton that we've drawn up to this point.

Nodes in a graph depict ''[[database record|record]]s'' in computer memory.  A record is a collection of data that can be conceived to reside at a specific ''[[memory address|address]]''.  For [[semiotics|semioticians]], an address can be recognized as a type of ''[[index]]'', and is commonly spoken of, on analogy with [[demonstrative pronouns]], as a ''[[pointer]]'', even among programmers who are otherwise innocent of semiotics.

Nodes in a graph represent ''records'' in computer memory.  A record is a collection of data that can be conceived to reside at a specific ''address''.  The address of a record is commonly described by programmers, on analogy with demonstrative pronouns, as a ''pointer'', and semioticians recognize it as a type of sign called an ''index''.

At the next level of concretion, a record/node can be represented as follows:

At the next level of concreteness, a record-node can be represented as follows:

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