chriseyre2000

chriseyre2000

Exploring Graphs with Elixir: Chapter 3 is missing some macros

Exploring Graphs with Elixir by @tonyhammond

I am unsure if the book is intended to be worked through to recreate the library (which is great for learning things).

When the macros are first used it includes use for both Graph and Query.
So far only the Graph using has been defined, and then it only creates the read_graph and write_graph methods.

First Post!

mvellandi

mvellandi

In
p.96 – Ch 3 > Storing Graphs in the Graph Store > Using Macros
the code comment in graph.ex

quote do
   # other (listings, new_graph) functions here
   def read_graph...
   def write_graph...
end

implies the author will define a few more functions later, or WE will add them on our own.

On the following page (97), we’re told we can check out the whole NativeGraph library functions:

iex> NativeGraph.[TAB]
...

which includes ALL the functions it will eventually output when ALL are defined in the using macros in both GraphCommons.Graph and GraphCommons.Query

The author just needs to update this code snippet to correspond with the next paragraph in the book.

Through the end of Ch 3, I see only two more functions used:
list_graphs
list_graphs_dir

which I started defining in the next subsection, where first used:
p.100 – Ch 3 > Storing Graphs in the Graph Store > Listing

NOTE: I just noticed the author didn’t include these two functions in the source code either.

Here’s what I additionally wrote in my GraphCommons.Graph using macro

quote do

      def list_graphs(file_test \\ :exists?) do
         GraphCommons.Graph.list_graphs(unquote(graph_type), file_test)
      end

      def list_graphs_dir(graph_dir) do
         GraphCommons.Graph.list_graphs_dir(graph_dir, unquote(graph_type))
      end

   def read_graph...
   def write_graph...

end

Where Next?

Popular Pragmatic Bookshelf topics Top

jdufour
Hello! On page xix of the preface, it says there is a community forum "… for help if your’re stuck on one of the exercises in this book… ...
New
raul
Page 28: It implements io.ReaderAt on the store type. Sorry if it’s a dumb question but was the io.ReaderAt supposed to be io.ReadAt? ...
New
adamwoolhether
When trying to generate the protobuf .go file, I receive this error: Unknown flag: --go_opt libprotoc 3.12.3 MacOS 11.3.1 Googling ...
New
leonW
I ran this command after installing the sample application: $ cards add do something --owner Brian And got a file not found error: Fil...
New
jskubick
I think I might have found a problem involving SwitchCompat, thumbTint, and trackTint. As entered, the SwitchCompat changes color to hol...
New
brunogirin
When I run the coverage example to report on missing lines, I get: pytest --cov=cards --report=term-missing ch7 ERROR: usage: pytest [op...
New
New
jonmac
The allprojects block listed on page 245 produces the following error when syncing gradle: “org.gradle.api.GradleScriptException: A prob...
New
creminology
Skimming ahead, much of the following is explained in Chapter 3, but new readers (like me!) will hit a roadblock in Chapter 2 with their ...
New
jwandekoken
Book: Programming Phoenix LiveView, page 142 (157/378), file lib/pento_web/live/product_live/form_component.ex, in the function below: d...
New

Other popular topics Top

Devtalk
Reading something? Working on something? Planning something? Changing jobs even!? If you’re up for sharing, please let us know what you’...
1062 22827 403
New
AstonJ
If it’s a mechanical keyboard, which switches do you have? Would you recommend it? Why? What will your next keyboard be? Pics always w...
New
AstonJ
Or looking forward to? :nerd_face:
503 14512 277
New
siddhant3030
I’m thinking of buying a monitor that I can rotate to use as a vertical monitor? Also, I want to know if someone is using it for program...
New
PragmaticBookshelf
Design and develop sophisticated 2D games that are as much fun to make as they are to play. From particle effects and pathfinding to soci...
New
Rainer
My first contact with Erlang was about 2 years ago when I used RabbitMQ, which is written in Erlang, for my job. This made me curious and...
New
AstonJ
poll poll Be sure to check out @Dusty’s article posted here: An Introduction to Alternative Keyboard Layouts It’s one of the best write-...
New
Exadra37
Oh just spent so much time on this to discover now that RancherOS is in end of life but Rancher is refusing to mark the Github repo as su...
New
PragmaticBookshelf
Author Spotlight Jamis Buck @jamis This month, we have the pleasure of spotlighting author Jamis Buck, who has written Mazes for Prog...
New
PragmaticBookshelf
A concise guide to MySQL 9 database administration, covering fundamental concepts, techniques, and best practices. Neil Smyth MySQL...
New

Sub Categories: