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by gorkish 2010 days ago
Love this, but the lack of interpretation of prefixed currency symbols is absolutely maddening! That it simply ignores the number and operand with no indication that these elements are ignored could easily lead to problems. I don't think I could in good conscience trust myself or those I might consider to be the target audience of this app to notice parsing errors in every case. Consider:

"$400 / 20" => 20 (ERROR)

"$400 / 25" => 25 (ERROR)

"400$ / 20" => 20 $ (OK)

"400$ / 25" => 16 $ (OK)
3 comments
bbodi 2010 days ago
In your case syntax highlighting helps. Everything which is not part of a calculation is rendered as a simple text (greyish): [image](https://trello-attachments.s3.amazonaws.com/558a94779b3b3c5d...)

But yes I admit it takes some time to get used to the colors and their meanings.

Currencies and exchange between them are on my feature list btw.

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gorkish 2010 days ago
Awesome; this is great to hear.

An idea you might consider is to display some kind of warning symbol or message if the input contains digits or operands which are not interpreted as part of the calculation that produces the output. This would have made the semantic meaning of the syntax highlighting immediately more evident.

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jannes 2010 days ago
It would also be nice to support other currency symbols. In Europe there are € and £, for example.

https://en.wikipedia.org/wiki/List_of_currencies_in_Europe

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vageli 2010 days ago
Your comment made me realize that most unit notation I'm familiar with has the unit as a suffix, with currency being the only standout that comes to mind.
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roywiggins 2010 days ago
It depends on the currency / country, too. Lots of countries put the currency afterwards, even "¢" comes after. $ and £ come before, but € ends up moving depending on the language.

https://en.wikipedia.org/wiki/Language_and_the_euro#Written_...

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gorkish 2010 days ago
Binary, ocatal and hexidecimal literals often are indicated with prefixes: 0b, 0 and 0x respectively. There are probably other esoteric cases that I can't think of off the top of my head. "Qty" is often prefixed, for instance. It's a complicated problem for a natural language calculator, to be sure. Here are a couple examples of ways to represent four thousand Canadian dollars that you might encounter and have no trouble interpreting as a human. This could be a good target for an ML tokenizer...

-$4000CAD

CA$-4,000.00

4.000,00CAD$

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