A standard way to branch control flow is to use an if statement.
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A simple if statement.
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let x = 10
if x == 10:
echo "x is 10"
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The other side of the if branch is else.
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let y = 11
if y == 10:
echo "y is 10"
else:
echo "y is not 10"
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Multiple branches can be specified by using elif between first if and
the final else.
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let name = "Mark"
if name == "Mark":
echo "Oh, hi Mark."
elif name == "Bob":
echo "What's up, Bob."
elif name == "Jane":
echo "Hi, Jane."
else:
echo "Hello there."
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if can also be used as an expression (i.e. performing a ternary operation).
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let is_ok = if true: "ok" else: "not ok"
echo is_ok
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| Conditions can be wrapped in parantheses. |
let i = 5
if (i > 5 and i < 10):
echo "i is between 5 and 10"
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| Variables can be defined before the condition. Scope of the variable is limited to the branch it was declared in. |
if (let j = 7; j < 5):
echo "j in scope: ", j
elif (let k = 8; k < 5):
echo "j not in scope, k in scope: ", k
else:
echo "neither j nor k in scope"
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$ nim c -r if_else.nim x is 10 y is not 10 Oh, hi Mark. ok neither j nor k in scope |
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