Daily Archives: 05.09.2017

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macOS disk image built with Qbs

Qbs (pronounced “Cubes”) is The Qt Company’s latest build tool, which is planned to be the replacement for qmake in the Qt 6 build system. In addition to its use within Qt, for our customers Qbs will also provide faster build times coupled with a rich feature set in order to reduce build engineering complexity and decrease time to market.

Today I’m excited to introduce you to the latest release of Qbs – 1.9. This is an important release with foundational new features.

What’s New?

In addition to the usual bug fixes and performance enhancements, this release includes two of the most foundational changes to the future of Qbs.

Language Improvements

The first of these is something we call Dependency Parameterization. Depends items can now be parameterized to set special module parameters for one particular product dependency. The new item type, Parameter, is used to declare such parameters in a module, while the new item type Parameters (note the ‘s’) is used to allow products to set default values for such parameters in their Export item.

So, what can dependency parameterization do for you? First, let’s step back and examine the meaning and usage of a Depends item.

Depends items are used to create a dependency between product A and product B, such that the target artifacts of the dependency can be used as inputs to the rules in the context of the depending product. In practice, Depends items have so far been used mostly to link an executable or library to another library. But a dependency is a very abstract concept, and can represent any type of relationship between two products. The fundamental problem is that whatever the meaning of the dependency, how that dependency took effect was only controllable from one side of the dependency relationship – the dependency’s side.

Qbs 1.9 allows this relationship to be controlled from the depending product’s side as well. For example, one of the products in your project may be a plugin which is implemented as a shared library. Your main application should depend on that plugin, because you want to ensure the plugin is built whenever the main application is, but you don’t want to directly link to that plugin because you want to load it entirely at runtime.

In Qbs 1.8, we would create a Depends items pointing to our shared library, like so:

Depends { name: "library" }

But there’s a problem – now our main application will actually link …read more

Source:: http://blog.qt.io/blog/2017/09/05/qbs-1-9-released/