John Daily macintux

This is not intended to be comprehensive or authoritative, just free online resources I've found valuable while learning more about Erlang.

Joe Armstrong's Swedish Institute of Computer Science homepage (Wayback Machine)

https://web.archive.org/web/20070429181654/http://www.sics.se/~joe/

Similar lists

Doc: http://www.erlang.org/doc/reference_manual/typespec.html

-type square() :: tuple(pos_integer(), pos_integer()).
-type side() :: 'white'|'black'.
-type movefun() :: fun((square(), square(), side()) -> tuple(square(), list(square()))).
-type movedef() :: tuple(atom(), movefun()).

-record(move, { piece,
 start,

I started working on some missing documentation in the Erlang stdlib, and found one particularly confusing rabbit hole.

gen_server.xml

In the documentation for gen_server, I found debug options for start_link which lacked type information:

    Dbg = trace | log | statistics | {logfile,FileName} | {install,{Func,FuncState}}</v>
        SOpts = [term()]

FileName isn't defined, Func and FuncState aren't defined, so I decided to dig into the source to document their types.

Put

API

Starting: https://github.com/basho/riak_kv/blob/1.4.2/src/riak_kv_wm_object.erl#L619
We create a new riak_object and populate the various fields with the headers, metadata supplied by the client.
Big suprise, we eventually call riak_client:put: https://github.com/basho/riak_kv/blob/1.4.2/src/riak_client.erl#L143
If/when the client returns any errors these are handled in handle_common_errors and it is nice to return human readable errors to client :)

Riak_client

Assuming you've created a text file named "ordered" with the PDFs in the sequence you'd like to create:

$ cp /System/Library/Automator/Combine\ PDF\ Pages.action/Contents/Resources/join.py /usr/local/bin/join-pdfs

$ perl -e '$first = <STDIN>; chomp $first; while(<STDIN>) { $index++; $intmdt = "foo$index.pdf"; chomp; system("join-pdfs -o $intmdt $first $_"); $first = $intmdt; }' < ordered

Now you'll have a host of foo.pdf files; the last one is the one you want to rename to something useful, then rm foo*.pdf.

	%%% @author John Daily
	%%% @copyright (C) 2013, John Daily
	%%% @doc
	%%%
	%%% @end
	%%% Created : 3 Aug 2013 by John Daily

	-module(etude51).
	-compile(export_all).

	#!/usr/local/bin/python

	import riak

	Riak = riak.RiakClient(pb_port=10017, protocol='pbc')
	TweetsBucket = Riak.bucket('tweets')

	results = TweetsBucket.get_index("hashtags_bin", "android",
	"androie", return_terms=True)

	#!/usr/local/bin/python

	import riak

	Riak = riak.RiakClient(pb_port=10017, protocol='pbc')
	TweetsBucket = Riak.bucket('tweets')

	results = TweetsBucket.get_index("hashtags_bin", "android",
	"androie", return_terms=False)

	curl -XPOST http://localhost:8098/mapred
	-H"Content-Type: application/json"
	-d '{"inputs":"notifications","query":[{"map":{"language":"erlang","source":"fun(O,_,_) when element(1,O) == r_object -> S=byte_size(term_to_binary(riak_object:get_values(O))), if (S>1048576) -> {ok,C}=riak:local_client(),C:delete(riak_object:bucket(O),riak_object:key(O)),[riak_object:key(O)]; true -> [] end;(_,_,_) -> [] end."}}]}'