Panther Value Stages

All expressions have a value stage which dictate which stage of compilation it may be used in.

Comptime

Comptime values are values that are known at compile-time and can be used as comptime expressions.

The following are runtime expressions:

• def variables
• template parameters
• comptime function calls with all parameters being comptime

Constexpr

The term "constexpr" in Panther does not have the same exact meaning as it does in C++. Constexpr values are values that may be used inside a comptime function but are not comptime themselves. Anywhere that requires a constexpr value also accept comptime values.

The following are runtime expressions:

• global const variables
• parameters in a comptime function
• return parameters in a comptime function
• error parameters in a comptime function
• const variables defined in a comptime function
• var variables defined in a comptime function
• comptime function calls with all parameters being comptime and/or constexpr (must have at least one constexpr parameter, or else it's comptime)

Runtime

Runtime values are values that may only be used at runtime as they are not known and/or cannot be calculated at compile-time. Anywhere that that requires a runtime value also accept constexpr and comptime values.

The following are runtime expressions:

• global var variables
• calls to external functions that are unknown / not linked in by the build system
• functions that have runtime values in their bodies
• var variables and const variables declared in function scope