61 lines
1.3 KiB
Plaintext
61 lines
1.3 KiB
Plaintext
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nix-repl> 1 + 1
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2
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nix-repl> :doc builtins.head
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Synopsis: builtins.head list
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Return the first element of a list; abort evaluation if
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the argument isn’t a list or is an empty list. You can
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test whether a list is empty by comparing it with [].
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nix-repl> f = a: "" + a
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Expect the trace to not contain any traceback:
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nix-repl> f 2
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error:
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… while evaluating a path segment
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at «string»:1:10:
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1| a: "" + a
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| ^
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error: cannot coerce an integer to a string: 2
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nix-repl> :te
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showing error traces
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Expect the trace to have traceback:
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nix-repl> f 2
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error:
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… from call site
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at «string»:1:1:
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1| f 2
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| ^
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… while calling anonymous lambda
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at «string»:1:2:
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1| a: "" + a
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| ^
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… while evaluating a path segment
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at «string»:1:10:
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1| a: "" + a
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| ^
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error: cannot coerce an integer to a string: 2
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Turning it off should also work:
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nix-repl> :te
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not showing error traces
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nix-repl> f 2
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error:
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… while evaluating a path segment
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at «string»:1:10:
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1| a: "" + a
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| ^
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error: cannot coerce an integer to a string: 2
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