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<div><a href="index.html" title="">Macaulay2Doc</a> > <a href="___The_sp__Macaulay2_splanguage.html" title="">The Macaulay2 language</a> > <a href="_getting_spinput_spfrom_spthe_spuser.html" title="">getting input from the user</a></div>
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<div><h1>getting input from the user</h1>
<div>The function <a href="_read.html" title="read from a file">read</a> can be used to prompt the user and obtain a line of input as a string. In response to the prompt, the user enters <tt>sample</tt> and press return.<table class="examples"><tr><td><pre>i1 : filename = read "file name : "
file name : sample
o1 = sample</pre>
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Let's use <a href="_peek.html" title="examine contents of an object">peek</a> to verify that this string contains no newline characters.<table class="examples"><tr><td><pre>i2 : peek filename
o2 = "sample"</pre>
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If necessary, we may use <a href="_value.html" title="evaluate">value</a> to evaluate the string provided by the user. In this example, we enter <tt>(x+y)^2</tt> in response to the prompt.<table class="examples"><tr><td><pre>i3 : R = ZZ[x,y];</pre>
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<tr><td><pre>i4 : s = read "polynomial : "
polynomial : (x+y)^2
o4 = (x+y)^2</pre>
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<tr><td><pre>i5 : value s
2 2
o5 = x + 2x*y + y
o5 : R</pre>
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