logo

Fansh

Overview

The fansh is a very simple interactive shell for exploring Fan. The shell allows you enter a one line statement or expression. If the result of the expression is non-void, then it will print the result via the Obj.toStr method. Enter "quit" to exit:

C:\dev\fan\bin\win>fansh
Fan Shell v1.0.19 ('?' for help)
fan> 3 + 4
7
fan> "3" + 4
34
fan> [3, 2, 9, 1].sort.join("|")
1|2|3|9
fan> quit

Scope

If you enter a statement which declares a local variable or assigns a local variable, the shell will make that variable available to subsequent evaluations. You can enter the "scope" command to list the current local variables. An example:

C:\dev\fan\bin\win>fansh
Fan Shell v1.0.19 ('?' for help)
fan> x := 5
5
fan> y := 7
7
fan> z := [x, y]
[5, 7]
fan> scope

Current Scope:
  sys::Int[] z = [5, 7]
  sys::Int y = 7
  sys::Int x = 5

Using Pods

You can use a fully qualified type name to import a pod:

fan> c := sql::Connection.open("jdbc:mysql://localhost:3306/sql_test", "root", "")
fan.sql.Connection@dc67e
fan> c.query("select * from Foo")

Limitations

Currently the Fan shell is quite limited compared to the shells of many other languages. You cannot enter a multi-line statement or expression. Also you cannot enter full type definitions. If you wish to explore the language using more than simple line statements, run your Fan code as a script.