dfgscript 0.2.0

A minimal, deterministic, LLM-friendly, line-based file manipulation DSL

DataForge v0.2

A minimal, deterministic, LLM-friendly, line-based file manipulation DSL.

Install

pip install dfgscript

Afterwards three entry points are available:

dataforge script.dfg          # canonical command
build     script.dfg          # alias matching the spec
py -m dataforge script.dfg    # module invocation

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Quick example

# notes.dfg
create-file "notes.txt"

1+Hello world
2+This is a test file
3+It has some content
4+End of file

dataforge notes.dfg           # write the file
dataforge notes.dfg --dry-run # preview without writing

---

CLI flags

Flag	Description
--dry-run / --preview	Show resulting file; do not write anything
--backup-dir PATH	Save a timestamped .bak copy before each write
--log PATH	Append log output to a file
--verbose / -v	Debug-level logging of every operation
--version	Print version and exit

---

DSL reference

File-level commands

create-file "path"   # create new — error if file exists
replace-file "path"  # unconditional overwrite
change-file "path"   # patch an existing file (creates if absent)

Line-level operations

N+<text>      # write/replace line N  (expands file with "" if N > length)
N-"<text>"    # delete line N  only if content matches exactly (warns otherwise)
N><text>      # insert <text> after line N  (shifts tail down)
$+<text>      # append as new final line

Comments & blank lines

# This is a comment

Blank lines in a .dfg are ignored; use N+ with empty text to create a blank line in the target file.

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Python API

from dataforge import parse, run

source = open("edit.dfg").read()
script = parse(source)                        # → DfgScript
lines  = run(script, dry_run=True)            # → list[str]
lines  = run(script, backup_dir=".backups")   # write + backup

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License

SOCL