02-28-2019
OpenSCAD is another purely functional language, though it doesn't look it at first. It looks more like C, with very different constraints on where you're allowed to do what. This causes a bit of brain damage at first ("why can't I overwrite variables!?" cried a million voices) but is good at illustrating what "functional language" means in a paradigm procedural programmers can understand. It's also got a nice orthogonal set of basic vector/matrix operations.
Having fought through and learned its ways, I agree that functional syntax is often simpler and more concise. It's rarely clearer -- comments are essential. And never in my experience have they ever been faster or smaller. Functional languages rely on things like compiler optimization and caching to reduce the amount of work for a given result. This amounts to big compilers/interpreters and occasionally unpredictable amounts of overhead. Tail recursion is a wondrous thing but so easy to poison!
That's the price you pay for a language one step closer to declaring what you want instead of declaring exactly how to do it. It's not a good fit for everything.
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SEQ(1) FSF SEQ(1)
NAME
seq - print a sequence of numbers
SYNOPSIS
seq [OPTION]... LAST
seq [OPTION]... FIRST LAST
seq [OPTION]... FIRST INCREMENT LAST
DESCRIPTION
Print numbers from FIRST to LAST, in steps of INCREMENT.
-f, --format=FORMAT
use printf style floating-point FORMAT (default: %g)
-s, --separator=STRING
use STRING to separate numbers (default:
)
-w, --equal-width
equalize width by padding with leading zeroes
--help display this help and exit
--version
output version information and exit
If FIRST or INCREMENT is omitted, it defaults to 1. FIRST, INCREMENT, and LAST are interpreted as floating point values. INCREMENT should
be positive if FIRST is smaller than LAST, and negative otherwise. When given, the FORMAT argument must contain exactly one of the printf-
style, floating point output formats %e, %f, %g
AUTHOR
Written by Ulrich Drepper.
REPORTING BUGS
Report bugs to <bug-coreutils@gnu.org>.
COPYRIGHT
Copyright (C) 2002 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICU-
LAR PURPOSE.
SEE ALSO
The full documentation for seq is maintained as a Texinfo manual. If the info and seq programs are properly installed at your site, the
command
info seq
should give you access to the complete manual.
seq (coreutils) 4.5.3 February 2003 SEQ(1)