diff --git a/lectures/figures/name_and_scope.drawio.svg b/lectures/figures/name_and_scope.drawio.svg new file mode 100644 index 0000000..aa124af --- /dev/null +++ b/lectures/figures/name_and_scope.drawio.svg @@ -0,0 +1,4 @@ + + + +
function
scope
length of name
variable
 \ No newline at end of file diff --git a/slides/12_clean_code.html b/slides/12_clean_code.html index 0886e9b..1577549 100644 --- a/slides/12_clean_code.html +++ b/slides/12_clean_code.html @@ -300,9 +300,9 @@

clean code

Clean Code: A Handbook of Agile Software Craftsmanship

by Robert C. Martin (2009) [2]

-
-

some recommendations are too specific to C-like languages

-
+
@@ -885,39 +885,82 @@

debug tables

-
-

use descriptive names

+
+

the inverse scope law of function names

+
+
+
+
+

The longer the scope of a function, the shorter its name +should be. Functions that are called locally from a few nearby +places should have long descriptive names, and the longest function +names should be given to those functions that are called from just one +place.

+

– Robert +C. Martin

+
+
+
+

“longer scope”: more general part of a code

+
+
+

+
+
+
+
+

function arguments

+
+
+
    -
  • a function does something, so it should start with an -imperative verb (imperative) +
  • do not use more than three [2]
    • +
+
+
    -
  • e.g., increaseSpeed
    • -
-
  • should be obvious what it does
    • -
  • The Inverse Scope Law of Function Names +
  • what if you’d need more?
      -
    • -

      Robert C. Martin The -Inverse Scope Law of Function Names: The longer the scope of a -function, the shorter its name should be. Functions that are called -locally from a few nearby places should have long descriptive names, and -the longest function names should be given to those functions that are -called from just one place.

      -
      • +
    • wrap it into an object
    • -
    -
    -

    function arguments

    + +
      -
    • do not use more than three
      • -
    • -

      Flag arguments are ugly […] loudly proclaiming that this function -does more than one thing [2].

      -
      • +
    • do not use flags +
        +
      • “Flag arguments are ugly […] loudly +proclaiming that this function does more than one thing [2].”
        • +
    +
    +
    +
    def build_empty_dataframe(start, end, cols):
+    records = []
+    for woy in range(start, end):
+        for dow in range(1, 8):
+            records.append([woy, dow, 0])
+    return pd.DataFrame.from_records(
+        records, columns=cols
+    )
    +
    +
    def query_progress(as_percentage: bool):
+    res = con.execute(progress_query)
+    progress = res.fetchone()[0]
+
+    if as_percentage:
+        return progress * 100
+    else:
+        return progress
    +
    +
    +

    no side effects

    @@ -961,28 +1004,28 @@

    prefer exceptions to returning error codes

    denoting blocks

    -
    for (i = 0; i < 10; i++) {
-    console.log(i);
-}
    -
    for (i = 0; i < 10; i++)
-    console.log(i);
    var a = 0;
-for (i = 0; i < 10; i++)
-    a++;
-    console.log(i);
    -
    -
    +class="sourceCode javascript">for (i = 0; i < 10; i++) { + console.log(i); +}
    for i in range(10):
-    print(i)
    +class="sourceCode javascript">for (i = 0; i < 10; i++) + console.log(i);
    a = 0
-for i in range(10):
-    a += 1
-    print(i)
    +class="sourceCode javascript">var a = 0; +for (i = 0; i < 10; i++) + a++; + console.log(i);
    +
    +
    +
    for i in range(10):
+    print(i)
    +
    a = 0
+for i in range(10):
+    a += 1
+    print(i)
    @@ -1000,24 +1043,24 @@

    denoting blocks

    puts i } ```--> -
    package main
- 
-import (
-    "fmt"
-)
- 
-func main() {
-    for i:=0; i<10; i++ {
-        fmt.Println(i)
-    }
-}
    -
    fn main() {
-    for i in 0..9 {
-        println!("{}", i);
-    }
-}
    +
    package main
+ 
+import (
+    "fmt"
+)
+ 
+func main() {
+    for i:=0; i<10; i++ {
+        fmt.Println(i)
+    }
+}
    +
    fn main() {
+    for i in 0..9 {
+        println!("{}", i);
+    }
+}
    @@ -1029,23 +1072,23 @@

    what could go wrong?

    parts from sslKeyExchange.c

    -
    if ((err = ReadyHash(&SSLHashSHA1, &hashCtx)) != 0)
-    goto fail;
-if ((err = SSLHashSHA1.update(&hashCtx, &clientRandom)) != 0)
-    goto fail;
-if ((err = SSLHashSHA1.update(&hashCtx, &serverRandom)) != 0)
-    goto fail;
-if ((err = SSLHashSHA1.update(&hashCtx, &signedParams)) != 0)
-    goto fail;
-    goto fail;
-if ((err = SSLHashSHA1.final(&hashCtx, &hashOut)) != 0)
-    goto fail;
    -
    fail:
-    SSLFreeBuffer(&signedHashes);
-    SSLFreeBuffer(&hashCtx);
-    return err;
    +
    if ((err = ReadyHash(&SSLHashSHA1, &hashCtx)) != 0)
+    goto fail;
+if ((err = SSLHashSHA1.update(&hashCtx, &clientRandom)) != 0)
+    goto fail;
+if ((err = SSLHashSHA1.update(&hashCtx, &serverRandom)) != 0)
+    goto fail;
+if ((err = SSLHashSHA1.update(&hashCtx, &signedParams)) != 0)
+    goto fail;
+    goto fail;
+if ((err = SSLHashSHA1.final(&hashCtx, &hashOut)) != 0)
+    goto fail;
    +
    fail:
+    SSLFreeBuffer(&signedHashes);
+    SSLFreeBuffer(&hashCtx);
+    return err;

    more about Apple’s “goto fail” fiasco (2014): [6], + + +
    function
    scope
    length of name
    variable
     \ No newline at end of file