Why Phobos is cool

[Jordan Wilson]

On Tuesday, 7 July 2020 at 23:38:26 UTC, Paul Backus wrote:
> On Monday, 6 July 2020 at 20:47:36 UTC, Jordan Wilson wrote:
>>
>> Just now I wanted to find the max value of a column in a text 
>> file, my thinking went "Excel? It'll take ages to load...I'll 
>> just google awk or something...hang on a minute, didn't I read 
>> somewhere about D oneliners?"
>>
>> echo 'import std; void main() { 
>> File("emu.sift","r").byLine.map!(a => a.splitter(" 
>> ").front.to!double).maxElement.writeln; }' | dmd -run -
>>
>> Thanks!
>>
>> Jordan
>
> IMO this still doesn't hold a candle to the awk version:
>
>     awk '{ if ($1 > max) max = $1 } END { print max }'
>
> With better library functions, though, the D version could be 
> much, much nicer. Something like:
>
>     stdin.byRecord.map(r => r.fields[0]).maxElement

Oh I agree the awk version is nicer (as is your theoretical D 
version). But I couldn't write that off the top of my head, 
whereas the D version I could.

Here's something I just did now that might be more relevant:
echo 'import std; void main() { 
"bets.json".readText.parseJSON.toPrettyString.writeln; }' | dmd 
-run - | more

I did this without looking up anything. Whereas before this 
echo/import std; into dmd -run trick, I would have opened up vim, 
and hoped that my previous command to pretty print was still in 
the history! (using python if I remember correctly).

I *think* that writing a more slightly more verbose D one-liner 
without needing to reference anything might prove itself useful 
to me in the long run, but we shall see.

Jordan