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Solidity / Events & Modifiers

indexed event parameter

Learn indexed event parameter in Solidity through a focused explanation, a dedicated construct-specific example, an engineering boundary, and a mastery check.

10 min read • Intermediate

indexed event parameter is an atomic Solidity topic inside Events & Modifiers. This lesson focuses on how the indexed event parameter construct is written, what it changes, and when it is the right tool.

Trace the example line by line. Identify the exact syntax for indexed event parameter, the input state before it runs, and the resulting value, control flow, database state, hardware behavior, or runtime effect afterward. Neighboring lessons use different constructs rather than renamed copies of this one.

Topic-specific example

solidity-06-02-indexed-event-parameter.sol
solidity Try It Live 
contract C { event Transfer(address indexed from,address indexed to,uint amount); }
Edge case / engineering note

For indexed event parameter, test the boundary that belongs to this exact feature rather than a generic failure case. Check invalid or empty input, NULL/unknown state, numeric limits, transaction or exception behavior, synthesis/runtime constraints, ownership/permission rules, or backtracking/control-flow effects where they apply.

Content source & attribution
Original Syntaxis Content · Original Syntaxis Content

Lesson quizzes

indexed event parameter Mastery Check →
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