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< h1 > < a href = "../../" > wren< / a > < / h1 >
< h2 > a classy little scripting language< / h2 >
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< li > < a href = "../" > Modules< / a > < / li >
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< h2 > core classes< / h2 >
< ul >
< li > < a href = "bool.html" > Bool< / a > < / li >
< li > < a href = "class.html" > Class< / a > < / li >
< li > < a href = "fiber.html" > Fiber< / a > < / li >
< li > < a href = "fn.html" > Fn< / a > < / li >
< li > < a href = "list.html" > List< / a > < / li >
< li > < a href = "map.html" > Map< / a > < / li >
< li > < a href = "null.html" > Null< / a > < / li >
< li > < a href = "num.html" > Num< / a > < / li >
< li > < a href = "object.html" > Object< / a > < / li >
< li > < a href = "range.html" > Range< / a > < / li >
< li > < a href = "sequence.html" > Sequence< / a > < / li >
< li > < a href = "string.html" > String< / a > < / li >
< li > < a href = "system.html" > System< / a > < / li >
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< td colspan = "2" > < h2 > core classes< / h2 > < / td >
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< li > < a href = "bool.html" > Bool< / a > < / li >
< li > < a href = "class.html" > Class< / a > < / li >
< li > < a href = "fiber.html" > Fiber< / a > < / li >
< li > < a href = "fn.html" > Fn< / a > < / li >
< li > < a href = "list.html" > List< / a > < / li >
< li > < a href = "map.html" > Map< / a > < / li >
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< li > < a href = "num.html" > Num< / a > < / li >
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< li > < a href = "range.html" > Range< / a > < / li >
< li > < a href = "sequence.html" > Sequence< / a > < / li >
< li > < a href = "string.html" > String< / a > < / li >
< li > < a href = "system.html" > System< / a > < / li >
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< h1 > System Class< / h1 >
< p > The System class is a grab-bag of functionality exposed by the VM, mostly for
use during development or debugging. < / p >
< h2 > Static Methods < a href = "#static-methods" name = "static-methods" class = "header-anchor" > #< / a > < / h2 >
< h3 > System.< strong > clock< / strong > < a href = "#system.clock" name = "system.clock" class = "header-anchor" > #< / a > < / h3 >
< p > Returns the number of seconds (including fractional seconds) since the program
was started. This is usually used for benchmarking. < / p >
< h3 > System.< strong > gc< / strong > () < a href = "#system.gc()" name = "system.gc()" class = "header-anchor" > #< / a > < / h3 >
< p > Requests that the VM perform an immediate garbage collection to free unused
memory. < / p >
< h3 > System.< strong > print< / strong > () < a href = "#system.print()" name = "system.print()" class = "header-anchor" > #< / a > < / h3 >
< p > Prints a single newline to the console. < / p >
< h3 > System.< strong > print< / strong > (object) < a href = "#system.print(object)" name = "system.print(object)" class = "header-anchor" > #< / a > < / h3 >
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< p > Prints < code > object< / code > to the console followed by a newline. If not already a string,
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the object is converted to a string by calling < code > toString< / code > on it. < / p >
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< div class = "codehilite" > < pre > < span > < / span > < span class = "vg" > System< / span > < span class = "o" > .< / span > < span class = "n" > print< / span > < span class = "p" > (< / span > < span class = "s" > " I like bananas" < / span > < span class = "p" > )< / span > < span class = "output" > I like bananas< / span >
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< / pre > < / div >
< h3 > System.< strong > printAll< / strong > (sequence) < a href = "#system.printall(sequence)" name = "system.printall(sequence)" class = "header-anchor" > #< / a > < / h3 >
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< p > Iterates over < code > sequence< / code > and prints each element, then prints a single newline
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at the end. Each element is converted to a string by calling < code > toString< / code > on it. < / p >
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< div class = "codehilite" > < pre > < span > < / span > < span class = "vg" > System< / span > < span class = "o" > .< / span > < span class = "n" > printAll< / span > < span class = "p" > ([< / span > < span class = "mi" > 1< / span > < span class = "p" > ,< / span > < span class = "p" > [< / span > < span class = "mi" > 2< / span > < span class = "p" > ,< / span > < span class = "mi" > 3< / span > < span class = "p" > ],< / span > < span class = "mi" > 4< / span > < span class = "p" > ])< / span > < span class = "output" > 1[2, 3]4< / span >
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< / pre > < / div >
< h3 > System.< strong > write< / strong > (object) < a href = "#system.write(object)" name = "system.write(object)" class = "header-anchor" > #< / a > < / h3 >
< p > Prints a single value to the console, but does not print a newline character
afterwards. Converts the value to a string by calling < code > toString< / code > on it. < / p >
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< div class = "codehilite" > < pre > < span > < / span > < span class = "vg" > System< / span > < span class = "o" > .< / span > < span class = "n" > write< / span > < span class = "p" > (< / span > < span class = "mi" > 4< / span > < span class = "o" > +< / span > < span class = "mi" > 5< / span > < span class = "p" > )< / span > < span class = "output" > 9< / span >
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< p > In the above example, the result of < code > 4 + 5< / code > is printed, and then the prompt is
printed on the same line because no newline character was printed afterwards. < / p >
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< p > Wren lives
< a href = "https://github.com/munificent/wren" > on GitHub< / a >
— Made with ❤ by
< a href = "http://journal.stuffwithstuff.com/" > Bob Nystrom< / a > and
< a href = "https://github.com/munificent/wren/blob/master/AUTHORS" > friends< / a > .
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