22. HTTP Project (pocket version)

TL;DR (5 lines)

A first program must be complete, not decorative.
The entry contract matters from the beginning.
A single procedure is enough to teach flow and failure.
The invalid example should isolate one structural mistake.
The goal is understanding the whole program shape, not memorizing tokens.

Concrete Problem

Beginners often see the first file as a bag of syntax instead of the smallest end-to-end executable program.

Coherent example

space demo/starting

proc greet(name: string) -> int {
  if name == "" { give 11 }
  give 0
}

proc main(args: list[string]) -> int {
  give greet("world")
}

export *

Complete examples

Each block below is a complete reading unit with its own boundary, data shape, and observable result.

Primary coherent example

This is the compact chapter anchor used by the surrounding explanation.

space demo/starting

proc greet(name: string) -> int {
  if name == "" { give 11 }
  give 0
}

proc main(args: list[string]) -> int {
  give greet("world")
}

export *

Small command program

This program has one helper, one guard, and one observable entry result.

space examples/starting/command

proc command_exit(name: string) -> int {
  if name == "" { give 64 }
  give 0
}

proc main(args: list[string]) -> int {
  give command_exit("build")
}

export *

First structured input

This version adds a form while keeping the executable path direct.

space examples/starting/input

form RunConfig {
  target: string
  verbose: bool
}

proc validate(cfg: RunConfig) -> int {
  if cfg.target == "" { give 11 }
  give 0
}

proc main(args: list[string]) -> int {
  let cfg: RunConfig = RunConfig { target: "demo", verbose: true }
  give validate(cfg)
}

export *

Immediate work for this chapter

Use one executable `proc main(args: list[string]) -> int` path.
Keep the first program minimal while still complete.
Make the exit code flow visible from helper to main.
Keep the first code block complete and aligned with current Vitte docs syntax.
Keep the invalid block focused on one broken contract only.
Replace generic prose with one concrete rule visible in the code.
Keep every example small enough to review from top to bottom.

Chapter override: 22-http-project.html

Dedicated problem

22. HTTP Project needs a concrete production-grade anchor around entry point, helper procedure, and returned status. The page should keep the examples, diagnostics, and review rules tied to that exact boundary instead of drifting back to generic tutorial prose.

Specific complete examples

22. HTTP Project chapter anchor

The primary example is promoted here as the first chapter-specific production reading unit.

space demo/starting

proc greet(name: string) -> int {
  if name == "" { give 11 }
  give 0
}

proc main(args: list[string]) -> int {
  give greet("world")
}

export *

Small command program

This program has one helper, one guard, and one observable entry result.

space examples/starting/command

proc command_exit(name: string) -> int {
  if name == "" { give 64 }
  give 0
}

proc main(args: list[string]) -> int {
  give command_exit("build")
}

export *

First structured input

This version adds a form while keeping the executable path direct.

space examples/starting/input

form RunConfig {
  target: string
  verbose: bool
}

proc validate(cfg: RunConfig) -> int {
  if cfg.target == "" { give 11 }
  give 0
}

proc main(args: list[string]) -> int {
  let cfg: RunConfig = RunConfig { target: "demo", verbose: true }
  give validate(cfg)
}

export *

Risks and diagnostics

Risk	Diagnostic signal	Action
Boundary drift	The chapter loses sight of entry point, helper procedure, and returned status.	Restate the boundary beside the first code block and every invalid case.
Generic prose	A paragraph would still be true in another chapter.	Replace it with a code-specific rule from this page.
Weak diagnostic	The failure does not point back to the chapter contract.	Reduce the invalid case until one failure explains the rule.

Review checklist

The first example is complete and aligned with Vitte docs syntax.
The production section names where this construct belongs in real code.
The risk table connects each failure to a diagnostic or review action.
The avoid list rejects broad misuse without adding quiz-like prompts.

Production use

Use this chapter when a code review needs to preserve entry point, helper procedure, and returned status.
Keep examples small enough to copy into fixtures or docs smoke tests.
Treat the invalid case as regression material for future docs checks.

What to avoid

Do not add a second topic that hides the chapter's main contract.
Do not expand examples by adding unrelated subsystems.
Do not rely on prose when a small Vitte block can show the rule.

Global explanation

The first chapter should prove one thing clearly: a Vitte project is an entry point, a small contract, and an observable result. That is enough to understand before learning richer constructs.

Invalid case

entry main {
  give 0
}

This invalid case stays small so the broken contract remains visible.

Common pitfalls

Teaching a first program as disconnected syntax fragments.
Adding too many concepts before the reader has one stable executable example.
Skipping the invalid case that explains why the entry contract matters.

Short exercise

Extend the example with one small data form and keep the same clean flow from input to exit code.

Summary in 5 points

A first program must be complete, not decorative.
The entry contract matters from the beginning.
A single procedure is enough to teach flow and failure.
The invalid example should isolate one structural mistake.
The goal is understanding the whole program shape, not memorizing tokens.

Next best action

Keep the example small, reproduce it locally, then continue to the full chapter if you need the broader context.

Chapter deep dive

22. HTTP Project turns the first file into a complete executable shape. The chapter is written for a beginner who needs one stable program before learning variants.

The practical boundary is: entry point, helper procedure, and returned status. Keep that boundary in view while reading the example, the invalid case, and the exercise.

Role in the learning path

Beginners often see the first file as a bag of syntax instead of the smallest end-to-end executable program.

The same first project grows from one entry point to a file with data, a procedure, a check, and one visible exit code.

This chapter helps a new reader build and understand the first complete Vitte program.

Profile-specific deep dive

First executable shape

The first program should show a complete path from helper to main.
The entry result should be obvious without extra tooling.
Avoid introducing advanced constructs before the first stable program.

Beginner contract

Keep names plain and domain-neutral.
Show one failure code before adding richer result types.
Preserve the exact syntax used by docs and tests.

Reading the valid example

space demo/starting: names the ownership boundary before any behavior appears.
proc greet(name: string) -> int {: states the callable contract: inputs first, result shape last.
if name == "" { give 11 }: guards a failure or edge case before the nominal result.
give 0: ends the local path with an explicit result.
}: supports the chapter contract without adding hidden behavior.
proc main(args: list[string]) -> int {: states the callable contract: inputs first, result shape last.
give greet("world"): ends the local path with an explicit result.
}: supports the chapter contract without adding hidden behavior.
export *: supports the chapter contract without adding hidden behavior.

Lesson from the invalid example

entry main {: this line helps isolate the failure because it marks the executable boundary where the example becomes observable.
give 0: this line helps isolate the failure because it ends the local path with an explicit result.
}: this line helps isolate the failure because it supports the chapter contract without adding hidden behavior.

Engineering decisions to preserve

Name the boundary before changing code: A first program must be complete, not decorative.
Keep the smallest example executable: The entry contract matters from the beginning.
Make the invalid path explain one failure only: A single procedure is enough to teach flow and failure.
Prefer a visible contract over an implied convention: The invalid example should isolate one structural mistake.
Leave a review anchor that another maintainer can verify: The goal is understanding the whole program shape, not memorizing tokens.

Context-specific review criteria

The page makes the entry point, helper procedure, and returned status boundary visible before the first code block.
The intended reader, a beginner who needs one stable program before learning variants, can follow the valid example through named contracts instead of memorized tokens.
The invalid example fails for the same reason the prose discusses.
The exercise extends the same contract instead of introducing an unrelated concept.
The next chapter can reuse the vocabulary introduced here without redefining it.
The chapter stays specific enough that its title materially changes the meaning of the page.
Every warning connects to a concrete code shape.
The summary leaves one durable engineering rule behind.

Contract matrix

Concern	Chapter rule	Evidence to keep
Ownership	Code belongs behind the boundary named by the chapter.	The chapter keeps ownership visible through entry point, helper procedure, and returned status.
Input contract	The procedure receives a shape that is named before branching.	The valid example names the accepted shape before branching.
Nominal path	The clean path remains readable without hidden state.	The successful result can be found without reading hidden state.
Failure path	The invalid case isolates one failure reason.	The broken example has one main reason to fail.
Naming	Names explain the domain rather than only the mechanism.	Names remain tied to the chapter goal.
Types	Types remove ambiguity from values and results.	Fields and return values carry domain meaning.
Control flow	Branches stay traceable from guard to result.	Guards appear before the result they protect.
Module boundary	The public surface stays smaller than implementation detail.	The public surface remains smaller than the implementation detail.
Diagnostic value	The failure path points back to the exact contract.	The invalid example points back to the exact contract.
Test value	Regression evidence covers one passing path and one failing path.	One passing case and one failing case cover the lesson.
Refactor value	Implementation cleanup preserves the result shape.	The result shape stays stable during local cleanup.
Publication value	The chapter leaves one concrete engineering rule.	The chapter leaves one concrete engineering rule.

Rewrite path for this chapter

Rewrite the opening paragraph so it names entry point, helper procedure, and returned status before naming syntax.
Keep the valid example small enough that the full contract fits on screen.
Move any broad claim back to a specific line in the example.
Preserve one invalid case that fails for the chapter's main reason.
Add one sentence explaining why the invalid case is not a random error.
Make every pitfall actionable by naming the code shape it damages.
Keep the exercise inside the same domain as the example.
Avoid introducing a second unrelated project just to show variety.
Use the summary to restate the chapter rule, not the table of contents.
Check that the next chapter can build on this vocabulary.
Remove any sentence that would still be true in every other chapter.
Keep the last action small, local, and testable.

Diagnostic anchors

The first inspected line is the one that declares the chapter's main contract.
The central type, field, procedure, or branch carries the chapter's main idea.
The invalid example includes a sentence-level explanation of its failure.
Refactors preserve the detail that would otherwise mislead a future reader.
The behavior that must stay stable is named before implementation changes begin.
Vague names are replaced before they become review friction.
Regression coverage protects the chapter's main contract.
Implementation details stay out of public API unless the chapter explicitly teaches that surface.
Beginner-facing diagnostics point to the contract, not to a random syntax detail.
The next chapter can assume one clearly named concept from this page.

When extending this chapter

Extend toward a beginner who needs one stable program before learning variants, not toward a broader catalog of features.
Add a second example only if it sharpens the same contract.
Prefer a small variant over a new subsystem.
Keep prose close to code; every abstract claim should point to a visible shape.
Do not hide a new concept in the exercise.
If a paragraph explains policy, add the concrete code boundary it protects.
If a paragraph explains syntax, add the semantic reason the syntax matters.
If a paragraph explains architecture, identify the owner of each boundary.
If a paragraph explains failure, keep the failing line close to the explanation.
Stop expanding when the chapter has one complete, testable lesson.

Failure modes to avoid

Teaching a first program as disconnected syntax fragments.
Adding too many concepts before the reader has one stable executable example.
Skipping the invalid case that explains why the entry contract matters.

Practice scenario

Start from the coherent example in 22. HTTP Project. Change one identifier, one guard, and one returned value. After each change, write down whether the public contract is still the same contract or a new one.

If the contract changed, update the type or result shape first. If only the implementation changed, keep the external name stable and add one regression note explaining what should not change again.

Before moving on

You can state the chapter role: turns the first file into a complete executable shape.
You can point to the main boundary: entry point, helper procedure, and returned status.
You can connect the invalid case to the problem statement: Beginners often see the first file as a bag of syntax instead of the smallest end-to-end executable program.
You can perform the exercise: Extend the example with one small data form and keep the same clean flow from input to exit code.