Results for “Ownership & optional values”
Small, practical examples. Search by task or narrow things down below.
Transpose an optional parsing result
Transpose an optional parsing result in a complete Rust program using the standard library.
Rust✓ Tested
Add context to a parsing failure
Add context to a parsing failure in a complete Rust program using the standard library.
Rust✓ Tested
Chain operations that may return None
Chain operations that may return None in a complete Rust program using the standard library.
Rust✓ Tested
Handle integer overflow without panicking
Handle integer overflow without panicking in a complete Rust program using the standard library.
Rust✓ Tested
Propagate a parsing error with question mark
Propagate a parsing error with question mark in a complete Rust program using the standard library.
Rust✓ Tested
Provide a default for a missing value
Provide a default for a missing value in a complete Rust program using the standard library.
Rust✓ Tested
Stop collecting when parsing fails
Stop collecting when parsing fails in a complete Rust program using the standard library.
Rust✓ Tested
Test missing values with IS NULL
Find rows where an optional value is absent.
IS NULL✓ Tested
Add an optional field to an existing table
SQL: A nullable column permits existing rows to remain valid while data is filled later.
SQL✓ Tested
Add an optional field to an existing table
SQL Server: A nullable column permits existing rows to remain valid while data is filled later.
SQL Server✓ Tested
Add an optional field to an existing table
Postgres: A nullable column permits existing rows to remain valid while data is filled later.
Postgres✓ Tested
Add an optional field to an existing table
SQLite: A nullable column permits existing rows to remain valid while data is filled later.
SQLite✓ Tested