Loop variable
A loop variable is a variable whose value represents, tracks, or controls the current iteration of a loop.
Get Programming: Learn to code with Python
A loop variable is a variable that receives successive items from a sequence during loop execution.
- How it is used
- Deploys loop variables to repeat a for-loop body across numeric sequences or string characters.
- How deep it goes
- Explains assignment and execution step by step, then contrasts automatic for-loop updates with manual while-loop control.
- Examples
- Uses range(3), character printing, string indices, counting exercises, and repeated-book messages as practice.
- What you can do after
- Apply it via Python for loops to process each number in a range or each character in a string.
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Learn Go with Pocket-Sized Projects
A loop variable is a variable whose value identifies or controls the current iteration of a loop.
- How it is used
- Protects values captured by goroutines launched inside loops.
- How deep it goes
- Explains the capture hazard and three protections, but does not develop loop-variable implementation internals.
- Examples
- Uses concurrent maze paths, channel messages, map and slice iteration, and parallel table tests.
- What you can do after
- Diagnose/debug with it by recognizing and preventing incorrect values captured by goroutines in loops.
Read how Learn Go with Pocket-Sized Projects explains loop variable →
Related concepts
- closureused by · A closure is a function or callable value together with access to bindings from the lexical environment in which it was created.
- loopused by · A loop is a programming control-flow construct that repeatedly executes a block of instructions according to an iteration rule or continuation condition.
- bindingkind of · Name binding is the association of an identifier with the program entity or value it denotes.
- lambdaaddressed by · A lambda is a language construct that defines an unnamed function or callable, often as a value.
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