Re: How to imporve D-translation of these Python list comprehensions ?
On Thursday, 1 February 2018 at 20:18:37 UTC, Ola Fosheim Grøstad
wrote:
On Monday, 15 January 2018 at 19:05:52 UTC, xenon325 wrote:
def aget(d, k1, k2):
return d.get(k1, {}).get(k2, '')
aa = ['ver', 'rev']
kk = set(chain(srv1.keys(), srv2.keys()))
dd = [dict(_name=k, **{a + str(i): aget(d, k, a) for a in
aa for i, d in enumerate([srv1, srv2])}) for k in sorted(kk)]
But that was really verbose, why didn't he contract everything
into one line?
dd = [dict(_name=k, **{a + str(i): d.get(k,{}).get(a,'') for a
in ('ver','rev') for i, d in enumerate((srv1, srv2))}) for k in
sorted(set(chain(srv1.keys(), srv2.keys(]
:*)
Rewritten in without comprehensions it is something like:
dd = []
for k in sorted(set(chain(srv1.keys(), srv2.keys(:
record = {'_name':k}
for a in 'ver','rev':
for i, d in enumerate((srv1, srv2)):
record[f'{a}{i}'] = d.get(k,{}).get(a,'')
dd.append(record)
Re: How to imporve D-translation of these Python list comprehensions ?
On Monday, 15 January 2018 at 19:05:52 UTC, xenon325 wrote:
def aget(d, k1, k2):
return d.get(k1, {}).get(k2, '')
aa = ['ver', 'rev']
kk = set(chain(srv1.keys(), srv2.keys()))
dd = [dict(_name=k, **{a + str(i): aget(d, k, a) for a in
aa for i, d in enumerate([srv1, srv2])}) for k in sorted(kk)]
But that was really verbose, why didn't he contract everything
into one line?
dd = [dict(_name=k, **{a + str(i): d.get(k,{}).get(a,'') for a in
('ver','rev') for i, d in enumerate((srv1, srv2))}) for k in
sorted(set(chain(srv1.keys(), srv2.keys(]
:*)
Re: How to imporve D-translation of these Python list comprehensions ?
On Thursday, 1 February 2018 at 11:59:23 UTC, Russel Winder wrote: On Mon, 2018-01-15 at 21:13 +, lobo via Digitalmars-d-learn wrote: On Monday, 15 January 2018 at 19:05:52 UTC, xenon325 wrote: > A workmate has recently shown this piece of code to show how > nice Python is (we are mostly C and growing C++ shop): > > [...] Well if that is what they can do in Python I'd hate to see their C++! They have done a great job making Python code read like Perl. This looks like something you'd see in an assignment at uni; "Decipher this Python code and port to your language of choice" :) Apart from the slur on Perl, I have to agree with this. Using a dreadful bit of Python code is the start of a downward spiral of expectation and programming in other languages. As noted earlier, I am working on a nicer rendering of this algorithm, and will be happy to share if people are interested. I'd be interested in seeing the result.
Re: How to imporve D-translation of these Python list comprehensions ?
On Mon, 2018-01-15 at 21:13 +, lobo via Digitalmars-d-learn wrote: > On Monday, 15 January 2018 at 19:05:52 UTC, xenon325 wrote: > > A workmate has recently shown this piece of code to show how > > nice Python is (we are mostly C and growing C++ shop): > > > > [...] > > Well if that is what they can do in Python I'd hate to see their > C++! They have done a great job making Python code read like > Perl. This looks like something you'd see in an assignment at > uni; "Decipher this Python code and port to your language of > choice" :) Apart from the slur on Perl, I have to agree with this. Using a dreadful bit of Python code is the start of a downward spiral of expectation and programming in other languages. As noted earlier, I am working on a nicer rendering of this algorithm, and will be happy to share if people are interested. -- Russel. === Dr Russel Winder t: +44 20 7585 2200 41 Buckmaster Roadm: +44 7770 465 077 London SW11 1EN, UK w: www.russel.org.uk signature.asc Description: This is a digitally signed message part
Re: How to imporve D-translation of these Python list comprehensions ?
On Mon, 2018-01-15 at 20:27 +, Igor Shirkalin via Digitalmars-d-
learn wrote:
> On Monday, 15 January 2018 at 19:05:52 UTC, xenon325 wrote:
> > A workmate has recently shown this piece of code to show how
> > nice Python is (we are mostly C and growing C++ shop):
> > dd = [dict(_name=k, **{a + str(i): aget(d, k, a) for a in
> > aa for i, d in enumerate([srv1, srv2])}) for k in sorted(kk)]
>
> This is the most terrible Python code I have ever seen.
> If you know Python, could you please unroll to more readable form?
Actually I have seen worse, but… I think the way this Python code is
presented is fairly dreadful.
I am fiddling with trying to provide a better version. If people are
interested in this I can share in a while when it's ready.
--
Russel.
===
Dr Russel Winder t: +44 20 7585 2200
41 Buckmaster Roadm: +44 7770 465 077
London SW11 1EN, UK w: www.russel.org.uk
signature.asc
Description: This is a digitally signed message part
Re: How to imporve D-translation of these Python list comprehensions ?
On 15.01.2018 20:05, xenon325 wrote:
I think, most clear code would be with tripple `foreach`, so I'll go
with that. But probably someone will come up with something better and
range-ier.
Suggestion are welcome!
import std.stdio, std.algorithm, std.range, std.array, std.conv,
std.json, std.typecons;
auto aa(R)(R r){
typeof(r.front[1])[typeof(r.front[0])] a;
foreach(x;r) a[x[0]] = x[1];
return a;
}
alias emap(alias a) = map!(x => a(x.expand));
void main(){
auto srv1 = [
"acs": ["ver": "1.2.3", "rev": "6f2260d"],
"cms": ["ver": "4.5", "rev": "b17a67e"],
"ots": ["ver": "6.7.80", "rev": "4f487d2"]];
auto srv2 = [
"acs": ["ver": "1.2.3", "rev": "6f2260d"],
"cms": ["ver": "5.1", "rev": "2a56c53"],
"vaa": ["ver":"0.7", "rev": "00852cb"]];
chain(srv1.keys, srv2.keys).sort.uniq
.map!(k => chain(only(tuple("_name", k)),
cartesianProduct(only("ver", "rev"),
only(srv1, srv2).enumerate)
.emap!((prop, srv) => tuple(text(prop,
srv.index), srv.value.get(k, null).get(prop, "")))
).aa).array.JSONValue.toPrettyString.writeln;
}
Re: How to imporve D-translation of these Python list comprehensions ?
On 15.01.2018 22:51, Timon Gehr wrote:
auto aa(R)(R r){
typeof(r.front[1])[typeof(r.front[0])] a;
foreach(x;r) a[x[0]] = x[1];
return a;
}
Actually, better to use std.array.assocArray.
import std.stdio, std.algorithm, std.range, std.array, std.conv,
std.json, std.typecons;
alias emap(alias a) = map!(x => a(x.expand));
void main(){
auto srv1 = [
"acs": ["ver": "1.2.3", "rev": "6f2260d"],
"cms": ["ver": "4.5", "rev": "b17a67e"],
"ots": ["ver": "6.7.80", "rev": "4f487d2"]];
auto srv2 = [
"acs": ["ver": "1.2.3", "rev": "6f2260d"],
"cms": ["ver": "5.1", "rev": "2a56c53"],
"vaa": ["ver": "0.7", "rev": "00852cb"]];
chain(srv1.keys, srv2.keys).sort.uniq
.map!(k => chain(only(tuple("_name", k)),
cartesianProduct(only("ver", "rev"),
only(srv1, srv2).enumerate)
.emap!((prop, srv) => tuple(text(prop,
srv.index), srv.value.get(k, null).get(prop, "")))
).assocArray).array.JSONValue.toPrettyString.writeln;
}
Re: How to imporve D-translation of these Python list comprehensions ?
On Monday, 15 January 2018 at 19:05:52 UTC, xenon325 wrote:
I think, most clear code would be with tripple `foreach`, so
I'll go with that. But probably someone will come up with
something better and range-ier.
I will admit clarity has suffered, but I like the brevity:
import std.json : JSONValue;
import std.array : array, assocArray;
import std.range : enumerate, byPair;
import std.algorithm : sort, joiner, map, uniq, each;
import std.typecons : tuple;
import std.conv : to;
import std.stdio : writeln;
unittest {
immutable srv1 = ["acs": ["ver": "1.2.3", "rev": "6f2260d"],
"cms": ["ver": "4.5", "rev": "b17a67e"], "ots": ["ver": "6.7.80",
"rev": "4f487d2"]];
immutable srv2 = ["acs": ["ver": "1.2.3", "rev": "6f2260d"],
"cms": ["ver": "5.1", "rev": "2a56c53"], "vaa": ["ver":"0.7",
"rev": "00852cb"]];
immutable keys = ["rev", "ver"];
immutable srvs = [srv1, srv2];
alias aget = (name, key) => srvs.map!(s => s.get(name,
[key:""])[key]);
alias bget = (name, key) => aget(name, key).enumerate.map!(b
=> tuple(key~b.index.to!string, b.value));
alias merge = (aa1, aa2) => (aa2.byPair.each!(kv =>
aa1[kv.key] = kv.value), aa1);
auto result = srvs
.map!(s => s.byKey)
.joiner
.array
.sort
.uniq
.map!(name => merge(keys.map!(key => bget(name,
key)).joiner.assocArray, ["_name": name]))
.array;
writeln(JSONValue(result).toPrettyString());
}
--
Simen
Re: How to imporve D-translation of these Python list comprehensions ?
On Monday, 15 January 2018 at 19:05:52 UTC, xenon325 wrote: A workmate has recently shown this piece of code to show how nice Python is (we are mostly C and growing C++ shop): [...] Well if that is what they can do in Python I'd hate to see their C++! They have done a great job making Python code read like Perl. This looks like something you'd see in an assignment at uni; "Decipher this Python code and port to your language of choice" :)
Re: How to imporve D-translation of these Python list comprehensions ?
On Monday, 15 January 2018 at 19:05:52 UTC, xenon325 wrote:
A workmate has recently shown this piece of code to show how
nice Python is (we are mostly C and growing C++ shop):
dd = [dict(_name=k, **{a + str(i): aget(d, k, a) for a in
aa for i, d in enumerate([srv1, srv2])}) for k in sorted(kk)]
This is the most terrible Python code I have ever seen.
If you know Python, could you please unroll to more readable form?
Suggestion are welcome!
---
Alexander
