activerecord change column default
def change
change_column_default :users, :name, "anonymous"
endlua escape special characters
Found a very good way of escaping punctuation characters in lua here
str:gsub ("%p", "%%%0")ecto simple update
u = Repo.get(User, 1)
# and to change it's updated_at
Repo.update!(u |> Ecto.Changeset.change(%{updated_at: Ecto.DateTime.utc}))elixir get information about a module
iex(2)> String.module_info
[module: String,
exports: [__info__: 1, downcase: 1, jaro_distance: 2, splitter: 2, strip: 2,
to_float: 1, rjust: 2, ends_with?: 2, contains?: 2, upcase: 1, at: 2,
equivalent?: 2, valid?: 1, reverse: 1, normalize: 2, splitter: 3,
replace_trailing: 3, graphemes: 1, last: 1, strip: 1, chunk: 2, ljust: 2,
ljust: 3, next_codepoint: 1, rstrip: 2, capitalize: 1, replace_suffix: 3,
printable?: 1, first: 1, match?: 2, lstrip: 2, replace_leading: 3,
split_at: 2, split: 2, length: 1, replace: 4, to_existing_atom: 1,
next_grapheme_size: 1, duplicate: 2, starts_with?: 2, rstrip: 1, slice: 3,
split: 1, valid_character?: 1, lstrip: 1, rjust: 3, slice: 2, to_atom: 1,
...], attributes: [vsn: [272593462254668022266866328062939769355]],
compile: [options: [:debug_info], version: '6.0.2',
time: {2016, 1, 14, 19, 20, 22},
source: '/home/geo/code/elixir/lib/elixir/lib/string.ex'], native: false,
md5: <<205, 19, 151, 86, 67, 198, 236, 82, 86, 152, 206, 221, 94, 34, 42, 11>>]elixir simple regex capture
iex(5)> q = "one 2 three 4 five"
"one 2 three 4 five"
iex(6)> Regex.match?(~r/\d+/, q)
true
iex(10)> Regex.scan(~r/(\d+)/, q)
[["2", "2"], ["4", "4"]]
iex(11)> Regex.scan(~r/(\d+)/, q, capture: :all_but_first)
[["2"], ["4"]]
iex(12)> Regex.scan(~r/(\d+)/, q, capture: :all_but_first) |> List.flatten
["2", "4"]multiline strings in lua
LuaJIT 2.1.0-alpha -- Copyright (C) 2005-2014 Mike Pall. http://luajit.org/
JIT: ON SSE2 SSE3 SSE4.1 fold cse dce fwd dse narrow loop abc sink fuse
> a=[[
>> one
>> two
>> three
>> ]]
> print(a)
one
two
three
>handling ctrl-c in a bash script
#!/bin/bash
trap ctrl_c INT
function ctrl_c() {
# do whatever cleanup you want here
}debugging elixir/phoenix tests
iex -S mix test path/to/your/test.exsAlso make sure that you have the proper require in your test:
defmodule YourApp.YourTest do
use ExUnit.Case
require IEx
# in case 60s is not enough
@tag timeout: 120000
test "it should work" do
# whatever
IEx.pry
# inspect
end
end