[HN Gopher] Compiler for "Easy" language from "Etudes for Progra...
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Compiler for "Easy" language from "Etudes for Programmers" book
(1978)
Author : begoon
Score : 25 points
Date : 2025-10-14 12:14 UTC (9 days ago)
(HTM) web link (github.com)
(TXT) w3m dump (github.com)
| dukoid wrote:
| I was assuming it's something similar to PL/0 but the grammar
| looks quite extensive...
| Joker_vD wrote:
| Basically Algol, but with gratuitous "SET" to simplify parsing
| assignment statements, and without generic "BEGIN" braces:
| those are baked into "DO"/"THEN"/"ELSE".
|
| You can probably straightforwardly translate it to Golang by
| running through a C preprocessor with an obvious set of macros.
| ape4 wrote:
| The "FI" for "endif" is like bash.
|
| The semicolons are like C.
|
| The "PROGRAM" section is like COBOL.
| kragen wrote:
| The "fi" thing arose during the Algol-68 process, which Steve
| Bourne participated in, which is why he put it in his shell.
| (He would have put "od" there too to terminate "do" if it
| wasn't already used for a hexdumper.) You also find it in, for
| example, Dijkstra's _Discipline of Programming_.
|
| Semicolons were widely used as statement separators in Algol-
| family languages, but in Easy they seem to be statement
| _terminators_ , so they _are_ apparently like C rather than
| like earlier Algol-family languages such as Pascal.
|
| Pascal also had the "program" thing. I'm not sure if earlier
| Algol languages did?
| IAmBroom wrote:
| COBOL precedes Pascal.
| kragen wrote:
| Yes, of course it does. I didn't mean to imply that COBOL
| got it from Pascal. I meant that the practice was much more
| widespread than just COBOL, and given that the rest of Easy
| is clearly an Algol-family language very similar to Pascal
| or (then-draft) Ada, that's probably where he got it.
| Rendello wrote:
| If you're Stephen R. Bourne, "FI" is also like C!
|
| (From the Bourne Shell source): https://www.tuhs.org/cgi-
| bin/utree.pl?file=V7/usr/src/cmd/sh...
| shrubble wrote:
| The Etudes book is considered a classic, especially among FSU
| programmers-the book was licensed for a small amount, translated
| into Russian and used in many classrooms.
| kragen wrote:
| It's absolutely a classic!
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(page generated 2025-10-23 23:01 UTC)