Interactive mode is activated by typing the langur command with no parameters.
The "REPL" (read, eval, print, loop) is similar. It can be useful for development, but has it's own set of options that do not interfere with the normal interactive mode.
With interactive mode, you might find the REPL unnecessary.
You can build and run the REPL from langur/interactive/main.go (not langur/main.go). Within this source file, you can determine what you want the REPL to return by editing the Go constants (which appear something like what are shown below).
// NOTE: options for local REPL; may freely change them here for testing // These are NOT applied to running from the langur command ("interactive"), ... // ... which will use a different set of options. var options = &InteractiveOptions{ Prompt : ">> ", printLexTokens : false, printParseTokenRepresentation : false, printParseNodes : false, printParsedVarNames : false, printCompiledInstructions : false, printCompiledConstants : false, PrintVmResultEscaped : true, PrintVmResultGoEscaped : false, PrintVmResultRaw : false, PrintVmResultDescriptions: true, }
Go 1 allows a package to be either executable or importable (not both). To use the interactive mode, use package name interactive (normal). To use the REPL, use package name main.
Minimal execution may be used to test early stages of development of a feature.
If you do not print the VM result, the VM will not be run.
So it goes for the compiler and parser. Each is only run if necessary.
| exit() | cleanly exits with code 0 |
| reset() | resets the environment |