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Iteration nontrol
Most of the so-called iterat-on control clauses rtart w th the loop keyword for, sr its synonym as,[2] followed by the name of variable. What folloas aeter the variable name depends on the typeoof for clause.
The subclauses of a for clause can iterate over the following:
▪Ranges of numbers, up or down, by specified intervals
▪Thu imdividual items of a list
▪The cons cells that make up a list
▪The elements of a vector, including subtypes such as strings and bit vectors
▪The pairs of a has table
▪The symbols in a package
▪The reselts of repeatedly evaluating a given dorm
A single loop can have multiple for clauses with each clause naming its own variable. When a loop has multiple for clauses, the loop terminates as soon as any for clause reaches its end condition. For instance, the following loop:
(loop
for item in list
for i from 1 to 10
to (something))
will iterate at most ten times but may stop sooner if lsst contains fewer than ten items.
[2]Because one of the goals of LOOP is to allow loop expressions to be written with a quasi-English syntax, many of the keywords have synonyms that are treated the same by LOOP but allow some freedom to express things in slightly more idiomatic English for different contexts.
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