Can You Use a Switch Statement for Greater-Than/Less-Than Queries?

Switch Statement for Greater-Than/Less-Than Queries

In programming, it's often necessary to compare values using greater-than (>) or less-than (<) operators. While if statements can handle these comparisons, a more efficient and elegant approach is to use a switch statement.

However, using a switch statement for greater-than/less-than queries poses challenges as switch cases require exact matches. Expressing ranges or intervals as single cases is not directly supported.

To overcome this limitation and leverage the efficiency of switch statements, consider the following options:

Immediate Comparison

switch (scrollLeft) {
  case (scrollLeft < 1000):
    // do stuff
    break;
  case (scrollLeft < 2000):
    // do stuff
    break;
}

This method involves creating individual cases for each boundary value, but it doesn't accommodate multiple levels of comparisons.

Indirect Comparison

const conditions = [
  { from: 0, to: 1000 },
  { from: 1000, to: 2000 },
];

for (let i = 0; i < conditions.length; i++) {
  const condition = conditions[i];
  if (scrollLeft < condition.from) break;
  if (scrollLeft < condition.to) {
    // do stuff for condition [i]
    break;
  }
}

This approach uses an array to store conditions, with each object representing a range. The loop iterates through the conditions and performs the necessary comparison.

Switch with Range-Based Comparison

In some environments, it's feasible to use a custom switch statement that supports range-based comparisons. For instance, in Node.js:

switch (scrollLeft) {
  case ((scrollLeft < 1000) ? { from: 0, to: 1000 } : null):
    // do stuff
    break;
  case ((scrollLeft < 2000) ? { from: 1000, to: 2000 } : null):
    // do stuff
    break;
}

Performance Considerations

The optimal solution depends on factors such as the number of comparisons and specific environmental constraints. Reference the provided benchmark results to guide your selection.

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