GenericJam
Cleaner alternative for nested case/cond/if statements?
I’m trying to find a cleaner coding style for what I’ve got happening repeatedly in my code right now. This is looking very pyramid of doom-ish
# Variables in scope
%{ var1: var1, var2: var2, var3: var3}
case function1(var1) do
# Success case one
{:ok, %{pattern1: _}} ->
case function2(var2) do
{:ok, %{pattern2: _}} ->
# Etc with the nesting as need be
Logger.info()
other ->
Logger.error("Oops")
end
# Success case two
{:ok, %{pattern3: _}} ->
case function3(var2) do
{:ok, %{pattern4: _}} ->
# Etc with the nesting as need be
Logger.info()
other ->
Logger.error("Oops")
end
# Failure case
other ->
Logger.error("He's dead, Jim. Cause of death: #{inspect(other)}")
end
I know that as an alternative I could put the pattern matching/fail catching in a series of functions but this isn’t necessarily any more readable as the functions should be grouped by name not by logical association. Once the logic gets more complicated, it is actually worse imo for readability.
Is there some alternative I’m missing?
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cnck1387
Just for future searches, would you mind including the with version so we have a before and after?
GenericJam
Here’s a rough translation although not direct as in the original I’ve got two success cases where only the first one will match whereas in the translation both with (potentially) match. This is the general idea though:
%{var1: var1, var2: var2, var3: var3}
with {:ok, %{pattern1: _}} <- function1(var1),
# Now you can use pattern1
{:ok, %{pattern2: _}} <- function2(%{pattern1: pattern1, var2: var2}) do
# Etc with the nesting as need be
Logger.info()
else
# Failure case
other ->
Logger.error("He's dead, Jim. Cause of death: #{inspect(other)}")
end
with {:ok, %{pattern3: _}} <- function1(var1),
{:ok, %{pattern4: _}} <- function3(var2) do
# Etc with the nesting as need be
Logger.info()
else
# Failure case
other ->
Logger.error("He's dead, Jim. Cause of death: #{inspect(other)}")
end
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