simple_env - Environment Variables for Eiffel

Overview

simple_env provides SCOOP-compatible environment variable access for Eiffel applications. Unlike the standard EXECUTION_ENVIRONMENT, it uses direct Win32 API calls with inline C for reliable, thread-safe environment manipulation.

Part of the Simple Eiffel ecosystem.

Quick Start

Installation

Set the environment variable:
```
export SIMPLE_EIFFEL=/d/prod
```

Add to your ECF file:

<library name="simple_env" location="$SIMPLE_EIFFEL/simple_env/simple_env.ecf"/>

Basic Usage

local
    env: SIMPLE_ENV
do
    create env

    -- Get a variable
    if attached env.get ("PATH") as path then
        print (path)
    end

    -- Set a variable
    env.set ("MY_VAR", "my_value")

    -- Expand paths
    print (env.expand ("%USERPROFILE%\Documents"))
end

Key Features

Get & Set

Read, write, and delete environment variables with simple API.

String Expansion

Expand %VAR% references in paths and strings.

Enumeration

List all variables or filter by prefix.

SCOOP Safe

Designed for concurrent programming with no shared state.

API Summary

Access

get (name) - Get variable value (Void if not set)
item [name] - Array-style access (alias for get)
has (name) - Check if variable exists

Modification

set (name, value) - Set environment variable
put (value, name) - Set (HASH_TABLE convention)
unset (name) - Remove environment variable

Expansion

expand (string) - Expand %VAR% references

Enumeration

all_names - All environment variable names
names_with_prefix (prefix) - Variables matching prefix

Why simple_env?

vs. EXECUTION_ENVIRONMENT

Feature	EXECUTION_ENVIRONMENT	SIMPLE_ENV
SCOOP compatible	No (internal caching)	Yes (no shared state)
String expansion	No	Yes (%VAR% support)
Enumerate variables	No	Yes (all_names, prefix filter)
Operation status	No	Yes (last_operation_succeeded)

Documentation

User Guide - Complete tutorial with examples
API Reference - Full API documentation
Architecture - Internal design and Win32 integration
Cookbook - Ready-to-use recipes