Angular–CompareWith

Angular 4 introduces a new directive that helps you compare select options. This directive is especially useful when your select options are dynamically populated.

Let’s explain why…

Here is a sample component that contains a dropdown with some options:

We set the default option by passing the object reference through the FormControl constructor. Problem is now that when we repopulate our options list(for example through an HTTP call), the object reference is gone and the model binding of our selected value is lost.

To solve this problem we can use the compareWith directive which will no longer compare the object references but uses a boolean expression or function instead:

Podman– Command execution failed with exit code 125

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A complex system designed from scratch never works

A few years ago, I worked as an architect on a big mainframe rewrite. I still count it as one of my failures. Not because the technology was wrong, but because I couldn't convince the management team to simplify the approach. Years later, the organization is still struggling to get the new system up and running. I left the project at the time, because I couldn't put my name behind an approach that would take very long and cost a lot of money without a working system to show for it along the way. Gall’s Law That memory keeps coming back to me, because it's a textbook case of Gall's Law playing out in real life. Gall's Law , from John Gall's Systemantics , states it plainly: A complex system that works is invariably found to have evolved from a simple system that worked. A complex system designed from scratch never works, and it cannot be patched to make it work. You have to start over with a simple system that works. What does that mean in practice,...

The art of simplicity

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