C Nlohmann Json Safe Generic Loader Template

What the source does

• FilesystemNone observedNo reads or writes in the source
• NetworkNone observedNo outbound calls in the source
• ShellNone observedNo commands run in the source
• DependenciesPinnedNothing floats
• SecretsNone foundNo keys in source

Five audit layers

Gates applied: no behavioural pass.

Audit 0.4.1 · source sha 04e912cff54b · 14 Oct 2026Report an issue or request a re-scan

• PublisherECNU-ICALK GitHub organizationOwner of the repository this skill is read from
• Source folderECNU-ICALK/AutoSkill/SkillBank/ConvSkill/english_gpt3.5_8_GLM4.7/c-nlohmann-json-safe-generic-loader-templateThe exact folder we audited
• LicenceNot declaredAs the repository states it
• Commit pinned for this verdict04e912cff54bA new audit runs when the source changes
• Repository statusNot archivedLast push 157 days ago
• Sandboxed runNot runSkills are read, not executed; layer L4 is skipped

Its description: Provides a C++ template function to load multiple variables from a nlohmann::json object safely, handling missing keys and type mismatches without causing crashes or syntax errors like C2760.

---
id: "b81f2ab2-84ee-4d1e-83a9-199ba2b3fda4"
name: "C++ nlohmann::json safe generic loader template"
description: "Provides a C++ template function to load multiple variables from a nlohmann::json object safely, handling missing keys and type mismatches without causing crashes or syntax errors like C2760."
version: "0.1.0"
tags:
  - "c++"
  - "nlohmann-json"
  - "template"
  - "error-handling"
  - "generic-programming"
triggers:
  - "c++ template load json"
  - "nlohmann json generic loader"
  - "prevent json crash missing key"
  - "fix C2760 nlohmann json"
  - "load many variables from json c++"
---

# C++ nlohmann::json safe generic loader template

Provides a C++ template function to load multiple variables from a nlohmann::json object safely, handling missing keys and type mismatches without causing crashes or syntax errors like C2760.

## Prompt

# Role & Objective
You are a C++ coding assistant. Your task is to provide a reusable template function to load variables from a `nlohmann::json` object into C++ variables.

# Operational Rules & Constraints
1. Create a template function `loadFromJson` that accepts a `const nlohmann::json& j`, a `const std::string& key`, and `T& var`.
2. The function must safely handle cases where the key is missing or the value type does not match the variable type.
3. Do NOT use the syntax `j[key].is<T>()` as it causes compiler error C2760.
4. Use `j.find(key)` to locate the key.
5. Use a `try-catch` block to attempt `it->get<T>()` to handle type conversion exceptions gracefully.
6. If the key is missing or conversion fails, the function should handle it silently or log it without crashing.

# Output
Provide the C++ code for the template function and an example of how to use it to load multiple variables.

## Triggers

- c++ template load json
- nlohmann json generic loader
- prevent json crash missing key
- fix C2760 nlohmann json
- load many variables from json c++

Excerpt, first 1,934 characters of SKILL.md, verbatim from the audited commit. It is text from someone else’s repository, quoted so you can judge it before your agent reads it.

git clone https://github.com/ECNU-ICALK/AutoSkill
git -C AutoSkill checkout 04e912cff54b

Works in

1. 2026-10-14
   ✓SAFE B 89 / 100

   first audit · source 04e912cff54b

Questions about C Nlohmann Json Safe Generic Loader Template

• github.com/ECNU-ICALK/AutoSkill/tree/main/SkillBank/ConvSkill/en — the audited source at commit 04e912cff54b and every finding aboveObserved · 14 Oct 2026

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