Filed under: Best Practices, Featured
  Comments: 1

This article provides a quick reference guide for learning Scheme and commonly used expressions. The target audience is for new NexJ developers who have previous programming experience.

Please refer to the Introduction to Scheme course for more in-depth discussion. Also, within NexJ Studio, you can mouse-over each function for details.


Description Scheme example Java equivalent
Boolean true #t true
Boolean false #f false
Null () null
Integer 100 100
String “John” “John”
Binary #z1234567890ABCDEF new byte[] {18,52,86,120,-112,-85,-51,-17};
Character #\A ‘A’
Symbol symbol  


Declaration and Assignment

Description Scheme example Java equivalent
Global scope variable
Assign value to variable
Limited scope variable
Limited scope variable with reference to previously defined variable

Boolean logic

Description Scheme example Java equivalent
Null Check
Equal Check
Not Equal Check



Description Scheme example Java equivalent
If statement
If…else statement (single line body)
If…else statement (multi-line body)
Multi-condition if statement
Ternary Operator
Non-Boolean Condition



Description Scheme example Java equivalent
Collection Lookup by Index
Collection Length
Collection Empty Check
List Lookup by Index
List Length
List Empty Check
Collection/List Lookup by Value

Collection/List Filtering

Collection/List Sorting




Description Scheme example Java equivalent
For loop through collection/list
For loop using index


Description Scheme example Java equivalent
Declare function
Caution: Last expression is always the return value

Invoke function

Declare function with variable arguments

Invoke function with variable arguments
Function Documentation


Description Scheme example Java/SQL equivalent
Object instantiation
Object instantiation with arguments
Object Update
Object Delete
Object Association
Single Object Read
Caution: Throws error if more than 1 record exists
Multi Object Read



Description Scheme example Java equivalent
Info-level logging
Debug-level logging
Error-level logging


Error Handling

Description Scheme example Java equivalent
Raise error
Assertion error
Try…Catch with restricted handler


Scheme Commands for Developers

Description Scheme example
Reset Scheme Console after metadata hotswap
Turn up SQL logging
Turn up RPC logging
Reseed Enumerations only


NexJ Studio Shortcuts

Description Shortcuts
Open file by name CTRL + SHIFT + D

This dialog includes files inherited from base models.

Open file by name CTRL + SHIFT + R

This dialog excludes files from base models.

File search by file content CTRL + H

Switch to “Model Search” tab

Execute selected text in Scheme Console CTRL + U
Select text between matching brackets CTRL + SHIFT + \
Auto code format CTRL + SHIFT + F
Code auto-complete CTRL + SPACE
Auto-indent as you type Window -> Preferences -> NexJ Studio -> Check “Auto-indent Scheme script as you type”
Delete current line CTRL + D
Block commenting CTRL + SHIFT + /
Rename variable ALT + SHIFT + R



  Comments: 1

  1. Hi,
    Good read material for quick reference! Very helpful.
    Just a suggestion – can you also include “how to get & set a class attribute in current context” to the above list?

    Aditya Phatak.

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