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Determine the format of the entrance pile at Ministerop: a guide
The miniscript is a popular programming language used to create decentralized applications on the POLKADOT network. When creating or compiling ministers, one of the crucial aspects that need to be understood is how the input pile shape is determined.
In this article, we will delve deeper into the concept of stack formats in the miniscrim and explore the implications of different call conventions by compiling a policy.
What is an input pile shape?
The input pile shape refers to the structure used by the compiler to represent the passed arguments for a function call. In other words, it is how the function carries their inputs from the environment and passes them as a result.
In the miniscript, the input pile shape is determined by the call convention of the function being called. The call convention defines how the function takes its inputs and passes them.
Types of call conventions
There are two main types of call conventions in the miniscript:
- Style C : This is the most common call convention, where each argument is passed as a separate value in the pile.
- Packed : In this convention, several arguments can be packed in a single pile slot.
Determine the input pile shape
By compiling a policy, the compiler must perform its own validity verification to ensure that the input pile shape corresponds to the expected call convention for each function call. The compiler uses this information to validate the inputs and outputs of the functions.
However, there is no unique “exact” or “universal” way to determine the input pile shape. Instead, the compiler should consult various sources, including:
1.
- Compiler Settings : Command and compilation settings can also influence the input pile shape.
Example of case use
Suppose we want to compile a policy that calls the function of ‘ministript-minicall’ with two arguments:
`CPP
Main () {
var arg1 = “Hello”;
VAR ARG2 = 42;
}
`
If we run the following command in our editor, we will see a summary of the input stack format:
`
> MINICALL MAIN
Minister Compiler: V0.11.6
Input pile shape:
ARG1 INT
ARG2 UINT8
INT result
`
From this output, we can determine that the minicall function expects two arguments on the stack, with the arah1being an integer and ARG2` being an unlawled integer of 256 bits.
Conclusion
Determining the input pile shape in the miniscript is a complex process that involves several factors, including function documentation, compiler settings and user input values. Although there is no single “universal” way to determine the input pile shape, understanding these sources of information can help you write a more robust and efficient code.
As developers, we must ensure that our policies follow the expected call conventions for each function call to avoid possible problems with input validation, data corruption or other problems.