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undefined method `source_index' for Gem:Module (NoMethodError)
...st ran into this problem myself while trying to upgrade an older Rails app from REE 1.8.7 to 1.9.3-p385. Oddly, Ruby 1.9.3-p327 works just fine. What it came down to was ruby-1.9.3-p385 had installed RubyGems version 2.0.2 for me, and 1.9.3-p327 has RubyGems v1.8.23 installed.
Gem.source_index has ...
RabbitMQ / AMQP: single queue, multiple consumers for same message?
...s it normally configured?
No, not if the consumers are on the same queue. From RabbitMQ's AMQP Concepts guide:
it is important to understand that, in AMQP 0-9-1, messages are load balanced between consumers.
This seems to imply that round-robin behavior within a queue is a given, and not conf...
How to return multiple values? [duplicate]
Is it possible to return two or more values from a method to main in Java? If so, how it is possible and if not how can we do?
...
Ruby : How to write a gem? [closed]
...g Rubygem projects. There's also a Gemcutter and Jeweler Railscast.
Hoe - From the guys at seattlrb.
gem-this adds a bunch of helpful rake tasks.
Some tutorials/guides:
Creating Your First Gem
Using bundler and rvm to build a rubygem - Using bundler and rvm to create a gem
Gem Packaging: Best P...
Calculate distance between two latitude-longitude points? (Haversine formula)
...s surface – using the
‘Haversine’ formula.
function getDistanceFromLatLonInKm(lat1,lon1,lat2,lon2) {
var R = 6371; // Radius of the earth in km
var dLat = deg2rad(lat2-lat1); // deg2rad below
var dLon = deg2rad(lon2-lon1);
var a =
Math.sin(dLat/2) * Math.sin(dLat/2) +
Ma...
Android Fragments: When to use hide/show or add/remove/replace?
...ill be in the running state of its lifecycle, but its UI has been detached from the window so it's no longer visible. So you could technically still interact with the fragment and reattach its UI later you need to. If you replace the fragment, the you are actually pulling it out of the container a...
AngularJS changes URLs to “unsafe:” in extension page
...
Note the file protocol is different from the blob protocol: $compileProvider.aHrefSanitizationWhitelist(/^\s*(https?|file|blob|ftp|mailto|chrome-extension):/);
– Arnaud Leyder
Jan 9 '15 at 14:31
...
What differences, if any, between C++03 and C++11 can be detected at run-time?
...
I got an inspiration from What breaking changes are introduced in C++11?:
#define u8 "abc"
bool isCpp0x() {
const std::string s = u8"def"; // Previously "abcdef", now "def"
return s == "def";
}
This is based on the new string literals t...
What does “hashable” mean in Python?
...
From the Python glossary:
An object is hashable if it has a hash value which never changes during its lifetime (it needs a __hash__() method), and can be compared to other objects (it needs an __eq__() or __cmp__() method...
Git command to display HEAD commit id?
... using these commands in a (large) git repo, I get two lines from git show-ref --heads and 6290 lines from git show-ref --head. so if you want just a single hash, this gives maybe not the intended result.
– Remigius Stalder
Jun 15 '17 at 8:47
...