Proctor It

To go with this weeks Ruby Tuesday post about Enumerable#include?, I decided I would highlight Erlang’s counterpart, lists:member/2. Sidebar for th [...]

[...] My goal of these Erlang Thursday’s for the next while will be to show off the “corresponding” functions in Erlang for the Ruby [...]

[...] of your favorite Erlang functions, or even just ones you would like to see a future Erlang Thursday post about? And don't forget to check out the last Tuesday's Ruby Tuesday on Enumerable# [...]

[...] Today’s Erlang Thursday function is lists:flatten/1. lists:flatten/1 flattens out an arbitrarily deep list of Erlang [...]

Today’s Erlang Thursday is lists:foldl/3 and lists:foldr/3. lists:foldl/3 is Erlang’s version of the reduce function. lists:foldl/3 takes a funct [...]

Today’s Erlang Thursday is lists:zip/2. lists:zip/2 returns a new list of two-tuples, from the corresponding elements of the two lists passed as ar [...]

Today’s Erlang Thursday is lists:partition/2. lists:partition/2 takes two arguments, a predicate function that will be called for every entry in th [...]

Today’s Erlang Thursday is on timer:tc/3. I am sure we have all written some timing code where we capture the current time, do something, capture t [...]

I was going to write up another method in the Ruby standard library, but was going to use the include? in some of the examples, so I decided I should [...]

Today’s Ruby function in Enumerable#max. Enumerable#max will find the largest item in an enum of items that are Comparable. This means it works ag [...]

Today’s Ruby Tuesday method is Enumerable#map, also known as Enumerable#collect. Enumerable#map is a function with a long lineage. Enumerable#map t [...]

Today’s Ruby Tuesday is Enumerable#reduce, also known as Enumerable#inject. Enumerable#reduce works against an enum and takes a initial value for t [...]

Today’s Ruby Tuesday is Array#flatten. Array#flatten returns a new array that has been recursively flattened into a one dimensional array. Ruby al [...]

Today’s Ruby Tuesday covers Enumerable#zip. Enumerable#zip weaves together elements of multiple Enumerables. It iterates through each item in the e [...]

Today’s Ruby Tuesday is on Benchmark::realtime. How many times have you written this Ruby method? And truthfully, how many different times have yo [...]

Today’s Ruby Tuesday is Proc#call. Procs are blocks of code that are bound to local variables, and as such, we need a way to be able to invoke them [...]

[...] Today’s Erlang Thursday is lists:dropwhile/2. lists:dropwhile/2 takes a predicate function and a list, and returns a list where the first series of items for which the predicate [...]

[...] Today’s Erlang Thursday function of the week is lists:any/2. lists:any/2 takes a predicate function as the first argument, and a list to iterate over as its second argument. lists:any/2 [...]

[...] Today’s Erlang Thursday is on lists:filter/2. lists:filter/2 takes two arguments, a predicate function and a list to iterate over. The return value is a list of items for which the predicate [...]

[...] Today’s Erlang Thursday is lists:partition/2. lists:partition/2 takes two arguments, a predicate function that will be called for every entry in the list, and returns a boolean value. The second [...]

[...] as well. On Functions in Erlang If you look at the first example above, you see that the first argument we are passing is fun(X) -> X + 1 end. This is Erlang’s syntax for an anonymous function. [...]

[...] . The erlang module also includes a version erlang:apply/2 that takes a function as it’s first argument, and a list of the arguments to be passed to the function as it’s second argument. While [...]

[...] Today’s Erlang Thursday is string:tokens/2. string:tokens/2 takes a string as the first argument, and a list of separators to split the string on, and returns a list of token strings. If [...]

[...] a function, an initial accumulator value, and a list, and returns a single value. The first argument given to foldl is a function that takes two arguments, the item currently iterating [...]

[...] , and a list to iterate over as its second argument. lists:any/2 returns true if the predicate function returns true for any of the elements in the given list, otherwise, lists:any/2 returns false. [...]

[...] . Unlike lists:filter/2, lists:dropwhile/2 stops checking the list as soon as the predicate function returns false. This means that elements for which the predicate function would return true can [...]

[...] two-tuple, with the first item in the tuple being the list of those items for which the predicate function returns true. The second item in the tuple is a list of those items for which the predicate [...]

[...] function and a list to iterate over. The return value is a list of items for which the predicate function returns true for that item. –Proctor [...]

[...] array of two arrays. The first item in the returned array is an array of items for which the block returns a truthy value. The second item in the returned array are the items for which the block [...]

[...] #select has a counterpart of Enumerable#reject which returns an array of items for which the block returns a falsey value. If all items are found to meet the criteria, Enumerable#reject returns an [...]

[...] Tuesday entry covers Enumerable#any?. Enumerable#any? takes a block and returns true if the block returns a truthy value for any of the elements in the enumeration, otherwise it returns false. The [...]

[...] items from the beginning of the enum up to, but not including, the first element for which the block returns a non-truthy value. Evaluation stops, and does not check the rest of the list if a falsey [...]

[...] returns a non-truthy value. Evaluation stops, and does not check the rest of the list if a falsey value is returned. This will leave other values in the list that might return a falsey value, unlike [...]

[...] value. The second item in the returned array are the items for which the block returns a falsey value. –Proctor [...]

[...] for all elements. While Enumerable#none checks the that return value of the block is a falsey value for all elements. Both Enumerable#all? and Enumerable#none? are both eager as well. – [...]

[...] counterpart of Enumerable#reject which returns an array of items for which the block returns a falsey value. If all items are found to meet the criteria, Enumerable#reject returns an empty array. – [...]

Today’s Erlang Thursday function is lists:flatten/1. lists:flatten/1 flattens out an arbitrarily deep list of Erlang terms, into a “flattened” [...]

Today’s Erlang Thursday function of the week is lists:any/2. lists:any/2 takes a predicate function as the first argument, and a list to iterate ov [...]