Elise: Bytecode-compiled DSL for typed data transformation pipelines

/eˈliːs/ → pronounced like “eh-LEES”

Grammar Rules, Todos, Documentation

Overview

A schema-driven data transformation language that compiles type-optimized bytecode from pipeline expressions over structured data. Write once, run against any conforming dataset.

File Types

NOTE: Only .csv files are supported for now.

Extension	Purpose
.eli	Source code
.elt	Schema / type definitions for input data
.csv	Input data file
.elc	Generated file with compiled bytecode

Execution Modes

1. Safe Direct Execution

elise --mode=run --source-code=sample.eli --data=data.csv --data-schema=data.elt

• Compiles in-memory (no .elc output)

• Performs full runtime validation of input data against schema

• Executes immediately

Safety: High

2. Unsafe Execution (Maximum Performance)

Step 1 — Build an executable

elise --mode=build --source-code=sample.eli --data-schema=data.elt --output=program.elc

Step 2 — Execute

elise --mode=exec --executable=program.elc --data=data.csv

• Requires precompiled .elc

• Skips runtime validation

• Executes fastest possible path

Use case: trusted, prevalidated data

Safety: None ⚠️

3. Validation-Only Step

elise --mode=validate --data=data.csv --data-schema=data.elt

• Full scan of data to ensure strict schema compliance

• Can be used before unsafe execution