#declarativeprogramming — Public Fediverse posts

#commonlisp #computerhistory #declarativeprogramming #declarativestyle #history #lisp

Vassil Nikolov | Васил Николов @[email protected] · 2026-05-01 · 07:55 UTC

#CommonLisp
#ComputerHistory
#DeclarativeProgramming
#DeclarativeStyle
#History
#Lisp
#ProceduralProgramming
#ProceduralStyle

Thank you!
Indeed your post is a good read and instructive on many counts.

Three notes:

(1)
«=====
(LOOP FOR X FROM 3 TO 5 COLLECT X)
(3 4 5)

(LOOP COLLECT X FOR X FROM 3 TO 5)
(3 4 5 6)
=====»

This is an important example (and a good catch), which has "procedural" written all over it and it shows that `loop' isn't actually declarative—it can only be viewed as such, carefully.

It seems to me that it would be interesting to fix the second case, rather than prohibit it, _but_ it may be difficult to justify the effort.
(Regrettably, I can't recall exactly what the _current_ Common Lisp specification says, but I'll check later.)

(2)
Yes, I have always found the design and history of the pathname system very instructive, in more ways than I can elaborate now.
And let no one forget about logical pathnames, too.

"LOSSAG" fit in a single 36-bit word, didn't it?

As a footnote, a long time ago I was something of a user of old IBM mainframe operating systems like VM/370¹, which did not have directories and separated a file name from a file type with a space (each up to eight characters, no lower case).
_________
¹ Bulgaria was lagging behind the technological times then.

(3)
It's interesting to mention an emulator in this context.
I can see a weak analogy to historical reconstructions.
(There are many people who do them, mostly as recreation.
I have been to some, watching horse riders shoot arrows and sheltering in a 7th-century-model tent from the rain.)

#commonlisp #computerhistory #declarativeprogramming #declarativestyle #history #lisp

Vassil Nikolov | Васил Николов @[email protected] · 2026-05-01 · 07:55 UTC

#CommonLisp
#ComputerHistory
#DeclarativeProgramming
#DeclarativeStyle
#History
#Lisp
#ProceduralProgramming
#ProceduralStyle

Thank you!
Indeed your post is a good read and instructive on many counts.

Three notes:

(1)
«=====
(LOOP FOR X FROM 3 TO 5 COLLECT X)
(3 4 5)

(LOOP COLLECT X FOR X FROM 3 TO 5)
(3 4 5 6)
=====»

This is an important example (and a good catch), which has "procedural" written all over it and it shows that `loop' isn't actually declarative—it can only be viewed as such, carefully.

It seems to me that it would be interesting to fix the second case, rather than prohibit it, _but_ it may be difficult to justify the effort.
(Regrettably, I can't recall exactly what the _current_ Common Lisp specification says, but I'll check later.)

(2)
Yes, I have always found the design and history of the pathname system very instructive, in more ways than I can elaborate now.
And let no one forget about logical pathnames, too.

"LOSSAG" fit in a single 36-bit word, didn't it?

As a footnote, a long time ago I was something of a user of old IBM mainframe operating systems like VM/370¹, which did not have directories and separated a file name from a file type with a space (each up to eight characters, no lower case).
_________
¹ Bulgaria was lagging behind the technological times then.

(3)
It's interesting to mention an emulator in this context.
I can see a weak analogy to historical reconstructions.
(There are many people who do them, mostly as recreation.
I have been to some, watching horse riders shoot arrows and sheltering in a 7th-century-model tent from the rain.)

#commonlisp #computerhistory #declarativeprogramming #declarativestyle #history #lisp

Vassil Nikolov | Васил Николов @[email protected] · 2026-05-01 · 07:55 UTC

#CommonLisp
#ComputerHistory
#DeclarativeProgramming
#DeclarativeStyle
#History
#Lisp
#ProceduralProgramming
#ProceduralStyle

Thank you!
Indeed your post is a good read and instructive on many counts.

Three notes:

(1)
«=====
(LOOP FOR X FROM 3 TO 5 COLLECT X)
(3 4 5)

(LOOP COLLECT X FOR X FROM 3 TO 5)
(3 4 5 6)
=====»

This is an important example (and a good catch), which has "procedural" written all over it and it shows that `loop' isn't actually declarative—it can only be viewed as such, carefully.

It seems to me that it would be interesting to fix the second case, rather than prohibit it, _but_ it may be difficult to justify the effort.
(Regrettably, I can't recall exactly what the _current_ Common Lisp specification says, but I'll check later.)

(2)
Yes, I have always found the design and history of the pathname system very instructive, in more ways than I can elaborate now.
And let no one forget about logical pathnames, too.

"LOSSAG" fit in a single 36-bit word, didn't it?

As a footnote, a long time ago I was something of a user of old IBM mainframe operating systems like VM/370¹, which did not have directories and separated a file name from a file type with a space (each up to eight characters, no lower case).
_________
¹ Bulgaria was lagging behind the technological times then.

(3)
It's interesting to mention an emulator in this context.
I can see a weak analogy to historical reconstructions.
(There are many people who do them, mostly as recreation.
I have been to some, watching horse riders shoot arrows and sheltering in a 7th-century-model tent from the rain.)

#proceduralstyle #proceduralprogramming #lisp #history #declarativestyle #declarativeprogramming

Vassil Nikolov | Васил Николов @[email protected] · 2026-05-01 · 07:55 UTC

#CommonLisp
#ComputerHistory
#DeclarativeProgramming
#DeclarativeStyle
#History
#Lisp
#ProceduralProgramming
#ProceduralStyle

Thank you!
Indeed your post is a good read and instructive on many counts.

Three notes:

(1)
«=====
(LOOP FOR X FROM 3 TO 5 COLLECT X)
(3 4 5)

(LOOP COLLECT X FOR X FROM 3 TO 5)
(3 4 5 6)
=====»

This is an important example (and a good catch), which has "procedural" written all over it and it shows that `loop' isn't actually declarative—it can only be viewed as such, carefully.

It seems to me that it would be interesting to fix the second case, rather than prohibit it, _but_ it may be difficult to justify the effort.
(Regrettably, I can't recall exactly what the _current_ Common Lisp specification says, but I'll check later.)

(2)
Yes, I have always found the design and history of the pathname system very instructive, in more ways than I can elaborate now.
And let no one forget about logical pathnames, too.

"LOSSAG" fit in a single 36-bit word, didn't it?

As a footnote, a long time ago I was something of a user of old IBM mainframe operating systems like VM/370¹, which did not have directories and separated a file name from a file type with a space (each up to eight characters, no lower case).
_________
¹ Bulgaria was lagging behind the technological times then.

(3)
It's interesting to mention an emulator in this context.
I can see a weak analogy to historical reconstructions.
(There are many people who do them, mostly as recreation.
I have been to some, watching horse riders shoot arrows and sheltering in a 7th-century-model tent from the rain.)

#Alchemy
#CommonLisp
#DeclarativeProgramming
#DeclarativeProgrammingStyle
#Lisp
#Loop
#LoopFacility

#commonlisp #computerhistory #declarativeprogramming #declarativestyle #history #lisp

Vassil Nikolov | Васил Николов @[email protected] · 2026-04-30 · 15:06 UTC

A primary source is a beautiful thing.

*

In my not so humble opinion, the finest uses of the Loop facility are those without `do' clauses.
Once I realized those are best viewed as if expressed in declarative style, I was no longer bothered by the "lack of parentheses".

Note that three years later Common Lisp specified `loop' while reserving forms with atoms in them, so it did specify enough for a REPL "in four".
(In REverse PoLish, of course;
WHOIS says that re.pl was created on 2000-03-14.)

#Alchemy
#CommonLisp
#DeclarativeProgramming
#DeclarativeProgrammingStyle
#Lisp
#Loop
#LoopFacility

#alchemy #commonlisp #declarativeprogramming #declarativeprogrammingstyle #lisp #loop

Vassil Nikolov | Васил Николов @[email protected] · 2026-04-30 · 15:06 UTC

A primary source is a beautiful thing.

*

In my not so humble opinion, the finest uses of the Loop facility are those without `do' clauses.
Once I realized those are best viewed as if expressed in declarative style, I was no longer bothered by the "lack of parentheses".

Note that three years later Common Lisp specified `loop' while reserving forms with atoms in them, so it did specify enough for a REPL "in four".
(In REverse PoLish, of course;
WHOIS says that re.pl was created on 2000-03-14.)

#Alchemy
#CommonLisp
#DeclarativeProgramming
#DeclarativeProgrammingStyle
#Lisp
#Loop
#LoopFacility

#alchemy #commonlisp #declarativeprogramming #declarativeprogrammingstyle #lisp #loop

Vassil Nikolov | Васил Николов @[email protected] · 2026-04-30 · 15:06 UTC

A primary source is a beautiful thing.

*

In my not so humble opinion, the finest uses of the Loop facility are those without `do' clauses.
Once I realized those are best viewed as if expressed in declarative style, I was no longer bothered by the "lack of parentheses".

Note that three years later Common Lisp specified `loop' while reserving forms with atoms in them, so it did specify enough for a REPL "in four".
(In REverse PoLish, of course;
WHOIS says that re.pl was created on 2000-03-14.)

#Alchemy
#CommonLisp
#DeclarativeProgramming
#DeclarativeProgrammingStyle
#Lisp
#Loop
#LoopFacility

#alchemy #commonlisp #declarativeprogramming #declarativeprogrammingstyle #lisp #loop

Vassil Nikolov | Васил Николов @[email protected] · 2026-04-30 · 15:06 UTC

A primary source is a beautiful thing.

*

In my not so humble opinion, the finest uses of the Loop facility are those without `do' clauses.
Once I realized those are best viewed as if expressed in declarative style, I was no longer bothered by the "lack of parentheses".

Note that three years later Common Lisp specified `loop' while reserving forms with atoms in them, so it did specify enough for a REPL "in four".
(In REverse PoLish, of course;
WHOIS says that re.pl was created on 2000-03-14.)

#Alchemy
#CommonLisp
#DeclarativeProgramming
#DeclarativeProgrammingStyle
#Lisp
#Loop
#LoopFacility

#loopfacility #loop #lisp #declarativeprogrammingstyle #declarativeprogramming #commonlisp

Vassil Nikolov | Васил Николов @[email protected] · 2026-04-30 · 15:06 UTC

A primary source is a beautiful thing.

*

In my not so humble opinion, the finest uses of the Loop facility are those without `do' clauses.
Once I realized those are best viewed as if expressed in declarative style, I was no longer bothered by the "lack of parentheses".

Note that three years later Common Lisp specified `loop' while reserving forms with atoms in them, so it did specify enough for a REPL "in four".
(In REverse PoLish, of course;
WHOIS says that re.pl was created on 2000-03-14.)