First-class functions/Use numbers analogously: Difference between revisions

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 </lang>
 - which has the same output.
+=={{header|BBC BASIC}}==
+{{works with|BBC BASIC for Windows}}
+<lang bbcbasic>      REM Create some numeric variables:
+      x = 2 : xi = 1/2
+      y = 4 : yi = 0.25
+      z = x + y : zi = 1 / (x + y)
+      REM Create the collections (here structures are used):
+      DIM c{x, y, z}
+      DIM ci{x, y, z}
+      c.x = x : c.y = y : c.z = z
+      ci.x = xi : ci.y = yi : ci.z = zi
+      REM Create some multiplier functions:
+      multx = FNmultiplier(c.x, ci.x)
+      multy = FNmultiplier(c.y, ci.y)
+      multz = FNmultiplier(c.z, ci.z)
+      REM Test applying the compositions:
+      x = 1.234567 : PRINT x " ", FN(multx)(x)
+      x = 2.345678 : PRINT x " ", FN(multy)(x)
+      x = 3.456789 : PRINT x " ", FN(multz)(x)
+      END
+      DEF FNmultiplier(n1,n2)
+      LOCAL f$, p%
+      f$ = "(m)=" + STR$n1 + "*" + STR$n2 + "*m"
+      DIM p% LEN(f$) + 4
+      $(p%+4) = f$ : !p% = p%+4
+      = p%</lang>
+'''Output:'''
+<pre>
+.234567            1.234567
+.345678            2.345678
+.456789          3.45678901
+</pre>
+Compare with the implementation of First-class functions:
+<lang bbcbasic>      REM Create some functions and their inverses:
+      DEF FNsin(a) = SIN(a)
+      DEF FNasn(a) = ASN(a)
+      DEF FNcos(a) = COS(a)
+      DEF FNacs(a) = ACS(a)
+      DEF FNcube(a) = a^3
+      DEF FNroot(a) = a^(1/3)
+      dummy = FNsin(1)
+      REM Create the collections (here structures are used):
+      DIM cA{Sin%, Cos%, Cube%}
+      DIM cB{Asn%, Acs%, Root%}
+      cA.Sin% = ^FNsin() : cA.Cos% = ^FNcos() : cA.Cube% = ^FNcube()
+      cB.Asn% = ^FNasn() : cB.Acs% = ^FNacs() : cB.Root% = ^FNroot()
+      REM Create some function compositions:
+      AsnSin% = FNcompose(cB.Asn%, cA.Sin%)
+      AcsCos% = FNcompose(cB.Acs%, cA.Cos%)
+      RootCube% = FNcompose(cB.Root%, cA.Cube%)
+      REM Test applying the compositions:
+      x = 1.234567 : PRINT x, FN(AsnSin%)(x)
+      x = 2.345678 : PRINT x, FN(AcsCos%)(x)
+      x = 3.456789 : PRINT x, FN(RootCube%)(x)
+      END
+      DEF FNcompose(f%,g%)
+      LOCAL f$, p%
+      f$ = "(x)=" + CHR$&A4 + "(&" + STR$~f% + ")(" + \
+      \             CHR$&A4 + "(&" + STR$~g% + ")(x))"
+      DIM p% LEN(f$) + 4
+      $(p%+4) = f$ : !p% = p%+4
+      = p%</lang>
 =={{header|C sharp|C#}}==