Enhancements Part 3: Implicit vs Explicit Enhancement Points

📌 KEY POINTS
✅ Explicit options (ENHANCEMENT-POINT / ENHANCEMENT-SECTION) are placed deliberately by SAP where extensions are expected.
✅ Implicit options exist automatically at the start/end of FORMs, function modules and methods, at the end of includes and in some declarations.
✅ Explicit points are more stable: SAP designed the context; implicit ones depend on internal code that may change.
⚠️ An ENHANCEMENT-SECTION implementation REPLACES SAP's code in that section — high risk.

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▶ WHERE WE ARE
Part 2 introduced both kinds. Now we compare them in detail to choose correctly.

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▶ 1. EXPLICIT ENHANCEMENT POINT
SAP source: ENHANCEMENT-POINT ep_xy SPOTS es_xy.

• Your code is inserted at that point (additional logic).
• Several implementations can exist and all run.
• SAP knows the context (available variables), so it tends to remain valid in upgrades.
• STATIC variant (ENHANCEMENT-POINT … STATIC) for declarations.

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▶ 2. EXPLICIT ENHANCEMENT SECTION
SAP source:
ENHANCEMENT-SECTION es_xy SPOTS es_spot.
… SAP code …

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▶ END-ENHANCEMENT-SECTION.

• Your implementation replaces the SAP code between the markers.
• Only one active implementation should replace a section.
• You own the replaced logic — SAP corrections to it no longer reach you.

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▶ 3. IMPLICIT ENHANCEMENT OPTIONS

• Start and end of FORM routines, function modules, methods (for methods: pre-/post-/overwrite-exit methods of global classes).
• End of includes, reports, structures (append fields in structures with care), end of the PUBLIC/PROTECTED/PRIVATE section of classes.
• Additional optional parameters for FMs and methods.
• Not available in the middle of a FORM, FM or method — only at these defined positions.

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▶ 4. HOW TO SEE THEM
Source editor → Enhance (spiral) → Edit → Enhancement Operations → Show Implicit Enhancement Options: markers appear as lines of quotes. Explicit points show as ENHANCEMENT-POINT statements.

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▶ 5. CHOOSING

• Explicit point exists at the right place → use it.
• Need to replace SAP logic → prefer a BAdI; an enhancement section only with strong justification.
• Only implicit fits → acceptable with care: small code, documentation, regression tests at every upgrade (Part 7).

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▶ STEP BY STEP

1. Search program SAPMV45A for ENHANCEMENT-POINT (Ctrl+F) and pick one inside an include.
2. Show implicit options in a FORM of the same program.
3. Compare: what data is available at each place (use the debugger).

✅ CHECKPOINT: you can distinguish explicit points, sections and implicit options and judge their risk.

A project replaced an ENHANCEMENT-SECTION for plant determination with its own code for one sales organisation. After a support package, SAP corrected the original logic in that section for another country, but the project's systems kept the old behaviour because the section was replaced.
The team moved the rule to an explicit point after the section (keeping SAP's logic and overriding the plant only for sales org 2000). SAP's correction became effective again, and the custom rule stayed.

• Replacing enhancement sections without re-implementing SAP logic.
• Believing implicit options exist anywhere in the code.
• Using implicit options when an explicit point or BAdI is available.
• Not checking other implementations at the same point.
• Assuming variables at an implicit point are stable across releases.

• Prefer explicit points and BAdIs.
• Avoid replacing sections; add logic after them instead.
• Keep plug-ins small and call classes.
• Retest implicit enhancements after every upgrade.
• Document why an implicit option was chosen.

Questions: "Implicit vs explicit enhancement?", "Enhancement point vs enhancement section?", "Where are implicit enhancement options?"
Strong answer: explicit points/sections are placed by SAP (ENHANCEMENT-POINT adds code, ENHANCEMENT-SECTION replaces code), stable context; implicit options exist automatically at start/end of FORMs/FMs/methods (pre/post/overwrite), end of includes, extra parameters; implicit are riskier across upgrades; prefer BAdI/explicit.