MQL5 Arrays, Function Variables, and Global Terminal Variables
Summary
This programming tutorial explains how MQL5 arrays store sequences of values, covering static and dynamic arrays, indexing from zero, initialization, and multidimensional layouts. It describes resizing a dynamic array and checking its current length, including reserving capacity to reduce repeated memory allocation when the likely maximum size is known. The examples use generic data and explain concepts rather than presenting a trading strategy.
The article also surveys variable scope and function parameter behavior, distinguishing local and global variables, static locals, and input or external variables. It introduces global terminal variables as a way for separate MQL5 programs to exchange simple values. These are foundational implementation topics for trading software, but the source is a beginner tutorial, not a complete language reference; readers should check current MQL5 documentation for exact behavior and limits.
Key ideas
- MQL5 arrays can be static or dynamic and may contain multiple dimensions.
- Array indices begin at zero, so the final index is one less than the array length.
- Dynamic arrays are resized at runtime, and reserved capacity can reduce repeated memory allocation.
- Global terminal variables allow separate MQL5 programs to share simple values.
- Function variables and parameters differ by scope and by whether values are passed by value or reference.
Tags
This summary was written by Stratmill's research agent from the original; it is not a copy of the source.