Lexical basics
Type system
Variables and assignment
Operators
Expression rules
Control flow
Functions
Built-in functions
None and NaN
Arithmetic
Algebra
Logarithmic and Exponential
Trigonometric
Rounding and Centering
Strings
Output, Formatting, and Errors
Dialogs, Clipboard, Platform, and Paths
Methods and properties
Built-in methods
Common Value Methods
Number Methods
String Basic Methods
String Slice Methods
String Parsing Methods
String Formatting Methods
String Regex Methods
String Trim and Case Methods
Objects
Built-in objects
Global objects
settings
session
python
Collections
array
map
data_array
File Format I/O
image_data
image_stream
Utils
crypto
timer
Comm
serial
Dialogs
file_open
file_save
msg_ok
msg_ok_cancel
msg_yes_no
msg_password
GUI objects
window
panel
group
splitpanel
label
textbutton
drawablebutton
togglebutton
togglegroup
textinput
textedit
numinput
slider
combobox
listbox
progressbar
led
separator
menu
image
snake
Classes and user-defined objects
Include system
Error model
Execution model and sessions
Host integration
Limits and performance
Formal reference
Glossary
Sidebar
Table of Contents
session
`session` is a built-in global object for inspecting and managing Expr sessions.
A session stores root variables, user-defined functions, user-defined classes, and the last result for a named evaluation context.
Properties
| Property | Type | Description |
|---|---|---|
| `current` | string | Name of the active session. The fallback session uses an empty name. |
print(session.current);
Methods
list()
Returns session names separated by new lines.
print(session.list());
list_variables()
Returns variables in the current session, one per line.
print(session.list_variables());
list_functions_builtin()
Returns built-in function names, one per line.
list_classes_builtin()
Returns built-in object constructor names, one per line.
list_functions()
Returns user-defined function names in the current session.
list_classes()
Returns user-defined class names in the current session.
create(name)
Creates a new session named `name`, switches the current context to it, and returns an OK result. If the session already exists, returns an error result.
session.create('job1'); print(session.current); // job1
delete(name)
Deletes the session named `name` and returns an OK result if it existed.
session.delete('old_job');
join(name)
Switches the current context to an existing session. If the session does not exist, an error is raised.
session.join('job1');
leave()
Switches the current context to the fallback empty-name session and returns an OK result.
session.leave();
clear()
Clears variables, user functions, and user classes from the current session. Built-in global objects are restored.
session.clear();
has_variable(sessionName, variableName)
Returns `true` if `sessionName` contains `variableName`.
exists = session.has_variable('job1', 'part_count');