3 ms·

Why dont they just take a string as the argument to search() and parse it? They could use a very SQL like Syntax: $collection = Braintree_Transaction::search

by icode 16y ago

Why dont they just take a string as the argument to search() and parse it? They could use a very SQL like Syntax: $collection = Braintree_Transaction::search(" orderId LIKE 'a2d%' AND customerWebsite LIKE '%.com' AND billingFirstName='John' AND status() IN ('AUTHORIZED','SETTLED') AND amount>=10 AND amount<=20.00) ");

rndmcnlly0 16y ago
One of the big reasons to build the DSL in the first place is to let the host language's syntax help you spot problems in your query. Syntax errors can be spotted from editor-provided syntax highlighting directly or slightly later when the code is read by the interpreter -- much sooner than when your runtime library finally decides to look at it (at search time).
st0p 16y ago
Yeah, i've never done any research into DSL's, but I always thought they would have some sort of custom syntax. Since DSL's seem quite the hype ATM, I'm a bit dissapointed by these examples. Sure, nice coding and all that (even though I would have used LINQ myself, but then again I'm not restricted to C# 2.0), but I fail to to see where the L of DSL comes into play. If this is the latest hype I didn't have time for to research, I'm not missing out.
- Lewisham 16y ago
  There are two types of DSLs, internal and external. External ones are the custom syntax you talk of, internal are DSLs that use features or quirks of a host language to appear different. XML or SQL are external DSLs, much of the cool Ruby stuff like Rake and Rails are internal DSLs. The examples presented are all internal (presumably for a good reason). There are advantages to both approaches. Read Martin Fowler's discussion at http://martinfowler.com/dslwip/ http://martinfowler.com/dslwip/
JadeNB 16y ago
Dan Bernstein argues that the most bug-prone part of a user-facing program is usually its parsing: see (5) of http://cr.yp.to/qmail/guarantee.html http://cr.yp.to/qmail/guarantee.html. chromatic summarises this as “Don't parse that string!” (http://www.modernperlbooks.com/mt/2010/07/dont-parse-that-string.html http://www.modernperlbooks.com/mt/2010/07/dont-parse-that-st...).

by icode 16y ago

rndmcnlly0 16y ago

One of the big reasons to build the DSL in the first place is to let the host language's syntax help you spot problems in your query. Syntax errors can be spotted from editor-provided syntax highlighting directly or slightly later when the code is read by the interpreter -- much sooner than when your runtime library finally decides to look at it (at search time).

st0p 16y ago

Yeah, i've never done any research into DSL's, but I always thought they would have some sort of custom syntax. Since DSL's seem quite the hype ATM, I'm a bit dissapointed by these examples. Sure, nice coding and all that (even though I would have used LINQ myself, but then again I'm not restricted to C# 2.0), but I fail to to see where the L of DSL comes into play. If this is the latest hype I didn't have time for to research, I'm not missing out.

Lewisham 16y ago
There are two types of DSLs, internal and external. External ones are the custom syntax you talk of, internal are DSLs that use features or quirks of a host language to appear different. XML or SQL are external DSLs, much of the cool Ruby stuff like Rake and Rails are internal DSLs. The examples presented are all internal (presumably for a good reason). There are advantages to both approaches. Read Martin Fowler's discussion at http://martinfowler.com/dslwip/ http://martinfowler.com/dslwip/

JadeNB 16y ago

Dan Bernstein argues that the most bug-prone part of a user-facing program is usually its parsing: see (5) of http://cr.yp.to/qmail/guarantee.html http://cr.yp.to/qmail/guarantee.html. chromatic summarises this as “Don't parse that string!” (http://www.modernperlbooks.com/mt/2010/07/dont-parse-that-string.html http://www.modernperlbooks.com/mt/2010/07/dont-parse-that-st...).