A Swift package for parsing and evaluating mathematical expressions.
The parser supports the basic math operators, variables and functions (defined in Swift). Under the hood it uses the wonder Owl Parser Generator https://github.com/ianh/owl.
Basic support for syntax coloring is provided in an extension of AttributedString
.
There are three main types in this package: Compiler
which compiles an expression string into CompiledProgram
and then Executor
which evaluates the CompiledProgram
. The Executor
can be reused for multiple expressions.
import SwiftCalc
let variables: [String: Value] = [
"pi": .number(.pi),
"sin": .function(Math.sin),
]
let program = try Compiler().compile("sin(1) * 10 * pi")
program.dump()
let executor = Executor(variables: variables)
let result = try executor.execute(program)
guard case let .number(resultValue) = result else {
fatalError()
}