LINQ: Why is it called "Comprehension Syntax"

Question

Why is the following LINQ syntax (sometimes called "query" syntax) called "comprehension" syntax? What's being comprehended (surely that's wrong)? Or, what is comprehensively represented (maybe I'm on the right track, now)?

Answer 1

It comes from the more language-agnostic term List Comprehension which many languages follow. The history apparently is:

The SETL programming language (later 1960s) had a set formation construct, and the computer algebra system AXIOM (1973) has a similar construct that processes streams, but the first use of the term "comprehension" for such constructs was in Rod Burstall and John Darlington's description of their functional programming language NPL from 1977.

FOLDOC mostly echoes this as well:

According to a note by Rishiyur Nikhil , (August 1992), the term itself seems to have been coined by Phil Wadler circa 1983-5, although the programming construct itself goes back much further (most likely Jack Schwartz and the SETL language).

The term "list comprehension" appears in the references below.

The earliest reference to the notation is in Rod Burstall and John Darlington's description of their language, NPL.

["The OL Manual" Philip Wadler, Quentin Miller and Martin Raskovsky, probably 1983-1985].

["How to Replace Failure by a List of Successes" FPCA September 1985, Nancy, France, pp. 113-146].

Answer 2

I suspect this is related to the second meaning of Comprehend:

to take in or embrace; include; comprise

This syntax has to do with defining what should be included in a set.

Answer 3

I think this paper can shed light http://dl.acm.org/citation.cfm?id=181564 I.e they argue and define (I think) what a comprehension syntax is. It is issued in 1994 and maybe it affected the design concepts of LINQ.