Equality Comparison of Floating-Point Numbers in C# (and Others)

tl;dr

You should compare two floating-point numbers for equality in C# as follows:

tolerance must be much larger than double.Epsilon.

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Implementing a System Tray App with WPF and MVVM

This article illustrates the implementation of a system tray application with WPF and the MVVM pattern. The full source code is in the GitHub repository.

The implementation has two distinctive points. First, it does not use notable WPF NotifyIcon because the license, CPOL, isn't compatible with any OSS licenses. Then, the implementation obeys the MVVM pattern and has no code behind.

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Quite Simple Memory Pool in C#

This article shows a quite simple memory pool to make a thread-unsafe library thread-safe without performance degradation in single-threaded programs. Same as the previous article, this article is about DynaJson.

Thread-safety requires overhead to allocate an instance by each invocation to isolate data being altered. Unless thread-safety is required, we can use a static class or a singleton to eliminate any additional allocation.

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How to Make JSON Parser Strict

I developed a JSON Parser for C# named DynaJson. It is very strict to the standard of RFC 8259. It accepts all conformant and rejects all non-conformant JSONs except for two exceptions.

One exception is trailing-commas. Another is leading 0 in numbers, for example, 02 and -02. The former is for practicality. The latter is for compatibility with DynamicJson.

JSON's grammar is simple, but carelessly implemented parsers don't accept all conformant and not reject non-conformant JSONs. An excellent article of Parsing JSON is a Minefield shows where mines are in implementing JSON parsers.

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