5 ms·

defn nested in defn seems totally wrong from a LISP (or Clojure) viewpoint. Isn't there a let or letfn? (Please note that I have no idea of Python)

deleted 13y ago
[deleted]
thaumasiotes 13y ago
in Python one function definition inside another is totally normal, and (to my knowledge) the statement doesn't generate a global binding, so that the inner-defined function is not accessible from outside the outer one. In other words, python's def appears to be syntactic sugar for variable assignment within whatever scope you're already in, except of course that there is no nonsugared form. Which would make it analogous to let, I believe.
- babarock 13y ago
  Technically, in Python nothing prevents you from writing something like: foo = lambda x: x*2 If only that lambda statements are limited (by design?) to only a single return expression. As far as Hy goes, lambdas won't have this limitation.
  - paultag 13y ago
    Totally. Hy will even auto-expand a lambda to a function if it's not sane Pythonically :)
  - nightpool 13y ago
    I totally write code like this all the time, when I need a quick one-liner that I don't really care about. A little more then a technicality.
- icebraining 13y ago
  In a way, there is: >>> mycode = "a = int(raw_input()); print a * 2; return a" >>> myfunc = FunctionType(compile(mycode, "<string>", "exec"), globals()) >>> myfunc() 4 8 4
  - wging 13y ago
    This SyntaxErrors for me. >>> from types import * >>> mycode = "a = int(raw_input()); print a * 2; return a" >>> myfunc = FunctionType(compile(mycode,"<string>","exec"), globals()) Traceback (most recent call last): File "<stdin>", line 1, in <module> File "<string>", line 1 SyntaxError: 'return' outside function Traceback (most recent call last): File "<stdin>", line 1, in <module> File "<string>", line 1 SyntaxError: 'return' outside function
hga 13y ago
It's not from a Scheme viewpoint, and specifically SICP, which is where he's starting from. Frankly, I'd prefer if it were idiomatic to locally defn inside Clojure defns, letfn is not hardly so elegant or clear. One of a number of areas where I find Clojure needlessly less tasteful and elegant than Scheme, but all are at least tolerable.

deleted 13y ago

[deleted]

thaumasiotes 13y ago

in Python one function definition inside another is totally normal, and (to my knowledge) the statement doesn't generate a global binding, so that the inner-defined function is not accessible from outside the outer one. In other words, python's def appears to be syntactic sugar for variable assignment within whatever scope you're already in, except of course that there is no nonsugared form. Which would make it analogous to let, I believe.

babarock 13y ago
Technically, in Python nothing prevents you from writing something like: foo = lambda x: x*2 If only that lambda statements are limited (by design?) to only a single return expression. As far as Hy goes, lambdas won't have this limitation.
- paultag 13y ago
  Totally. Hy will even auto-expand a lambda to a function if it's not sane Pythonically :)
- nightpool 13y ago
  I totally write code like this all the time, when I need a quick one-liner that I don't really care about. A little more then a technicality.
icebraining 13y ago
In a way, there is: >>> mycode = "a = int(raw_input()); print a * 2; return a" >>> myfunc = FunctionType(compile(mycode, "<string>", "exec"), globals()) >>> myfunc() 4 8 4
- wging 13y ago
  This SyntaxErrors for me. >>> from types import * >>> mycode = "a = int(raw_input()); print a * 2; return a" >>> myfunc = FunctionType(compile(mycode,"<string>","exec"), globals()) Traceback (most recent call last): File "<stdin>", line 1, in <module> File "<string>", line 1 SyntaxError: 'return' outside function Traceback (most recent call last): File "<stdin>", line 1, in <module> File "<string>", line 1 SyntaxError: 'return' outside function

hga 13y ago

It's not from a Scheme viewpoint, and specifically SICP, which is where he's starting from. Frankly, I'd prefer if it were idiomatic to locally defn inside Clojure defns, letfn is not hardly so elegant or clear. One of a number of areas where I find Clojure needlessly less tasteful and elegant than Scheme, but all are at least tolerable.